rear camber correction for 1991-2005 acura nsx

Rear Camber Correction for 1991-2005 Acura NSX

A Baccalaureate thesis submitted to the Department of Mechanical and Materials Engineering

College of Engineering and Applied Science University of Cincinnati

in partial fulfillment of the

requirements for the degree of

Bachelor of Science

in Mechanical Engineering Technology

by

Mitchell Backscheider

April 2014

Thesis Advisor: Professor Ahmed Elgafy, Ph.D.

ii

ACKNOWLEDGEMENTS

Sponsor: Faxon Machining CNC Milling

Tradesman: Dave Hentz Welding & Tube Bending

TABLE OF CONTENTS

ACKNOWLEDGEMENTS ...................................................................................................... II

TABLE OF CONTENTS .......................................................................................................... II

LIST OF FIGURES ................................................................................................................ III

LIST OF TABLES .................................................................................................................. IV

ABSTRACT ............................................................................................................................. V

INTRODUCTION AND RESEARCH ..................................................................................... 1

PROBLEM STATEMENT........................................................................................................................................ 1 INTERVIEWS ....................................................................................................................................................... 2 DOUBLE WISHBONE SUSPENSION ....................................................................................................................... 3 CAMBER ............................................................................................................................................................. 4 DALI RACING NON-COMPLIANCE REAR BEAM .................................................................................................. 5 CEDAR RIDGE FABRICATION REAR BEAM BUSHINGS ......................................................................................... 6 AYOTTE TECHNOLOGIES OFFSET UPPER CONTROL ARM BUSHINGS .................................................................. 7 HARDRACE PILLOWBALL REAR UPPER ADJUSTABLE CONTROL ARMS .............................................................. 8 HARDRACE REAR ADJUSTABLE LOWER CONTROL ARM .................................................................................... 9

CUSTOMER FEEDBACK, FEATURES AND OBJECTIVES ............................................ 10

SURVEY ANALYSIS ........................................................................................................................................... 10 PRODUCT FEATURES AND OBJECTIVES ............................................................................................................. 11 ENGINEERING CHARACTERISTICS ..................................................................................................................... 13

CONCEPT GENERATION AND SELECTION ................................................................... 14

STANDARD BUSHING SELECTION ....................................................................................................................... 14 UNIVERSAL BALL JOINT SELECTION .................................................................................................................. 14 RELOCATED AXIS MOUNTING BRACKET ............................................................................................................ 15 2 PIECE SHOULDER MOUNTING BRACKET .......................................................................................................... 15 BILLET SLIDING-ADJUSTABLE ARM ................................................................................................................... 15 TUBULAR FIXED LENGTH ARM .......................................................................................................................... 16

CALCULATIONS .................................................................................................................. 17

CALCULATING THE FORCES IN THE CONTROL ARM ............................................................................................ 17 FREE BODY DIAGRAM........................................................................................................................................ 18

FABRICATION AND ASSEMBLY ...................................................................................... 20

MANUFACTURING PROCESSES ........................................................................................................................... 20 CORROSION RESISTANCE ................................................................................................................................... 24 FINAL ASSEMBLY .............................................................................................................................................. 25

TESTING ................................................................................................................................ 26

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TESTING PROCESS ............................................................................................................................................. 26 TESTING RESULTS ............................................................................................................................................. 27

SCHEDULE AND BUDGET ................................................................................................. 28

SCHEDULE ........................................................................................................................................................ 28 BUDGET ............................................................................................................................................................ 28

CONCLUSION ....................................................................................................................... 29

WORKS CITED ..................................................................................................................... 30

APPENDIX A – RESEARCH ................................................................................................ 31

APPENDIX B – CUSTOMER SURVEY .............................................................................. 37

APPENDIX C – QUALITY FUNCTION DEPLOYMENT (QFD) ...................................... 38

APPENDIX D – PRODUCT OBJECTIVES .......................................................................... 39

APPENDIX E – SCHEDULE ................................................................................................ 41

APPENDIX F – BUDGET ..................................................................................................... 42

APPENDIX G – DETAIL DRAWINGS ................................................................................ 43

LIST OF FIGURES Figure 1 – Double Wishbone Suspension ................................................................................. 3

Figure 2 – Camber .................................................................................................................... 4

Figure 3 – Dali Racing Non-Compliance Rear Beam .............................................................. 5

Figure 4 – Cedar Ridge Fabrication Rear Beam Bushings ....................................................... 6

Figure 5 – Ayotte Technologies Offset Bushings ..................................................................... 7

Figure 6 – Hardrace Honda S2000 Rear Camber Kit ............................................................... 8

Figure 7 – Hardrace Nissan 240sx Lower Control Arm ........................................................... 9

Figure 8 - Energy Suspension 16.3104G Bushings ................................................................ 14

Figure 9 - QA1 Chromalloy XMR Series Rod End ................................................................ 14

Figure 10 – Relocated Axis Mounting Bracket ...................................................................... 15

Figure 11 – 2 Piece Shoulder Mounting Bracket .................................................................... 15

Figure 12 – Fixed Length Camber Correction Arm................................................................ 16

Figure 13 – Selected Components in Assembly ..................................................................... 16

Figure 14 – Free Body Diagram 1 .......................................................................................... 18

Figure 15 – Free Body Diagram 2 .......................................................................................... 19

Figure 16 – Mandrel Bent and Saw Cut Parts......................................................................... 20

Figure 17 – Turned Sleeves and Inserts .................................................................................. 20

Figure 18 – Turned and Honed Bushing Housing .................................................................. 21

Figure 19 – Radius Notched Joint ........................................................................................... 21

Figure 20 – Alignment Bar ..................................................................................................... 22

Figure 21 – Turned Mounting Brackets .................................................................................. 22

Figure 22 – CNC Milled Mounting Brackets ......................................................................... 22

Figure 23 – Tack Welded Joints ............................................................................................. 23

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Figure 24 – Complete GTAW Joint Detail ............................................................................. 23

Figure 25 – Complete GTAW Welded Control Arm .............................................................. 24

Figure 26 – Powder Coated Finish ......................................................................................... 24

Figure 27 – Installed Component ............................................................................................ 25

Figure 28 – Testing Jig ........................................................................................................... 26

Figure 29 – Deflection Measurement ..................................................................................... 26

Figure 30 – Testing Results .................................................................................................... 27

Figure 31 – Schedule Overview .............................................................................................. 28

LIST OF TABLES Table 1 – Survey Results ........................................................................................................ 10

Table 2 – Engineering Characteristics .................................................................................... 13

Table 3 – Compressive Force Components ............................................................................ 18

Table 4 – Tensile Force Components ..................................................................................... 19

Table 5 – Testing Data ............................................................................................................ 27

Table 6 – Budget ..................................................................................................................... 28

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ABSTRACT

A consistent problem with lowered Acura NSX’s is that the tire alignment values stray

outside of the factory determined specifications. These alignment errors in addition to the

lack of replaceable wear components make for increased maintenance expenses. A

redesigned upper control arm that offers replaceable wear components with the addition of

camber correction was designed and tested to meet the needs set forth by potential customers.

The vast majority of those surveyed stated that the top qualities they would like to see

included in the design of a replacement control arm include replaceable wear components,

safety, reliability, durability and ease of maintenance. A few attempts have been designed to

correct camber angle on these vehicles, but in short all have added harshness to the vehicle’s

ride quality and did not address the problem of the wear components.

A fixed camber correction was built into the length of the new control arm, which takes

into account the angle which the arm pivots on the vehicle. This makes for a true camber

correction, perpendicular to the vehicle. By replacing only the upper control arm, the factory

camber adjustment cam bolt is retained for fine tuning the camber angle.

The upper control arm was designed to target the customer needs. Replacing the aging

factory upper control arm with the newly designed upper control arms will offer the customer

a variety of options for the life of the vehicle. New standard polyurethane bushings and

universal rod ends make for readily available replacement parts. The control arm was

designed to be a bolt on and go package to the customer. Hardware has been specified in

such a manner that no special tooling or modification is needed while installing these control

arms, and all torque specifications align with those set forth by the factory service manual.

Rear Camber Correction for 1991-2005 Acura NSX Mitchell Backscheider

1

INTRODUCTION AND RESEARCH

PROBLEM STATEMENT

The Acura NSX was produced by Honda Motor Corporation from 1990 through 2005. It

offered a mid-engine, rear wheel drive powertrain in an all-aluminum body. Honda's race

track innovation and competitive history were displayed on the road and track by the NSX's

ultra-rigid, ultra-light all aluminum chassis and front and rear double wishbone suspension,

with forged control arms connected to forged alloy wheels. This was the world's first

production car engine to contain titanium connecting rods, forged pistons, and ultra-high-

revving capabilities; the redline was at 8,000 rpm, producing a peak horse power of 270. All

of these characteristics result in the NSX containing many traits which are usually associated

with track and race engineered motor cars (1).

While many people argue that the NSX was one of the best handling cars available at its

time, there are always people looking to push these limits. Like with many things, enthusiasts

are always looking for ways to modify and improve characteristics that Engineers have spent

so much time perfecting. The first modification that many NSX owners look to do is to lower

the car, which is done by replacing the shock/spring bodies. Unfortunately this modification

changes the geometry of many other suspension components which can negatively affect

handling characteristics. Although if corrected, a lower center of gravity is a very effective

on the track, especially when the suspension offers adjustable dampening and rebound.

This project will consist of redesigning and creating a rear upper wishbone control arm,

which will add the ability to correct camber, one of the most important characteristics of

wheel alignment which determines the amount of contact area the tire will have on the road.

This adjustable arm will replace the original cam adjustment bolts in regards to camber

correction, and offer a wider range of camber adjustment to accommodate for the increase in

camber caused by lowering the vehicle.


2

INTERVIEWS

Brian Urlage has 21 years of experience in the car industry. He opened Source1

Automotive in 2006, where they are now known nation-wide as a leader in Performance

NSX modification and maintenance. Brian notes that the aftermarket support for the NSX is

substantially less than many other often modified automobiles. Brian sees camber issues

often, as there is no cost effective way to manage this issue on customer’s vehicles. Brian

notes that being able to manage camber issues for customer will improve tire wear for

customers that simply want to drive their cars, along with improving traction in straight line

racing and light turns. He sees there being a high demand for this product if quality and ease

of adjustment is there. He stated that NSX owners do not mind paying for a quality product

that allows for ease of installation and improves troublesome issues such as camber (2).

Andrew Nguyen has been building cars for 14 years. Andrew enjoys the exterior of the

NSX the most, as he feels it was so ahead of its time appearance-wise. He would like to see

camber adjustment that allows for running wider wheel/tire combinations with the best

contact patch. Also for quick adjustment depending on the type of driving or racing he is

taking part in. He prefers sliding style ball joint’s as they offer quick and easy adjustment of

camber. Cost of parts is not an issue to Andrew, as he is most concerned about durability and

ease of adjustment (3).

After understanding what a few potential customers would like to see in a camber

solution for the Acura NSX, I was able to explore the various products available and what

advantages and disadvantages various products offered.

See Appendix A for complete research.


3

DOUBLE WISHBONE SUSPENSION

The Acura NSX utilizes Double Wishbone Suspension in the front and rear of the

vehicle. The wheel spindles are supported by an upper and lower 'A' shaped arm as shown in

Figure 1. In this type of suspension the lower arm carries most of the load. When looking

head-on at this type of suspension, what you'll find is that it's a very parallelogram system

that allows the spindles to travel vertically up and down. When they do this, they also have a

slight side-to-side motion caused by the arc that the wishbones describe around their pivot

points. This side-to-side motion is known as scrub (4). There are two other types of motion

of the wheel relative to the body when the suspension articulates; camber and toe.

.

Figure 1 – Double Wishbone Suspension

The Acura NSX utilizes a shorter upper wishbone and a longer lower wishbone. This

design allows for camber to increase more negative as the wheel travels upward relative to

the body. While this is great from a handling aspect, this camber is also increased when the

body of the vehicle is lowered. This lowering creates negative static camber values resulting

in less tire contact with the road. Typically this camber should be adjusted during a tire

alignment to obtain the factory alignment specifications.

Camber is typically adjustable from the factory, although it is usually limited.


4

CAMBER

Camber is a tire alignment variable that is viewed from the front of the vehicle. Camber

describes the inward or outward tilt of the tire. The illustration in Figure 2 shows whether

this tilt is referred to as positive or negative. The camber adjustment maximizes the tire-to-

road contact and takes into account the changes of force when a vehicle is turning. Due to the

vertical line always remaining perpendicular to the body, camber is the one adjustment that

can be set according to driving habits. Generally, if you drive more aggressively when

cornering, more negative camber can be set. If you drive on highways and do very little hard

cornering, more positive camber can be set (5).

Figure 2 – Camber

Depending on the vehicle’s design, the amount of camber adjustment can be limited.

Common factory installed camber adjustments include cam bolts, turnbuckles and shims. The

Acura NSX utilizes cam bolts at the rear lower control arm rear mounting point. Due to the

angle of the wishbone mounting points, adjusting this one cam bolt can move the bottom of

the hub in or out depending on the desired alignment settings. The problem arises from the

limited amount of adjustment at this cam bolt, specifically on vehicles that have been

lowered from the factory ride height.

A few companies have created solutions to increase the amount of camber adjustment on

the Acura NSX.


5

DALI RACING NON-COMPLIANCE REAR BEAM

Dali Racing offers a service to correct rear camber for customers. They require the rear

beam of the customer’s NSX to be sent to them, where they will then replace it with a Non-

Compliance Rear Beam. They offer two levels of camber correction, depending on what the

customer wants.

The Non-Compliance Rear Beam involves removing the customer’s original rubber

bushings, and replacing them with solid Aluminum components with an offset center hole.

This allows the original alignment cam bolt to be utilized for fine tuning of the camber as

shown in Figure 3.

Figure 3 – Dali Racing Non-Compliance Rear Beam

Dali Racing does not recommend use of this camber correction for street use, as it

replaces one compliant aspect of the suspension with a non-compliance part (6).

The next option for camber correction on Acura NSX’s is Cedar Ridge Fabrication’s

Rear Beam Bushings.


6

CEDAR RIDGE FABRICATION REAR BEAM BUSHINGS

Cedar Ridge Fabrication also offers Rear Beam Bearings. Similar to Dali Racing,

these bearings and sleeves replace the original rubber bushings in the rear beam of the NSX.

They utilize an offset center hole, to allow more camber adjustment at the factory alignment

cam bolt as shown in Figure 4.

Figure 4 – Cedar Ridge Fabrication Rear Beam Bushings

They offer the components separately, or as a service depending on the customer’s

needs. Cedar Ridge Fabrication also offers complementing components to the Rear Beam

Bearings. They include the following: Front Lower Bearings, Rear Upper A-Arm Bearings

and Rigid Toe Links.

Utilizing Cedar Ridge’s entire selection of suspension components makes for a solid

non-compliance rear suspension. All of the original rubber bushings are replaced with solid

non-compliance parts. This is ideal for a strictly race car, as the dynamic alignment settings

will vary only by ride height and not by rubber bushing deformation (7).

The next option for camber correction on Acura NSX’s is Ayotte Technologies Offset

Upper Control Arm Bushings.


7

AYOTTE TECHNOLOGIES OFFSET UPPER CONTROL ARM BUSHINGS

Ayotte Technologies takes a slightly different approach than the aforementioned

companies. They correct camber by replacing the rear upper control arm’s axial compliant

bushings with non-compliant self lubricating polymer bearing material mated to a billet T6-

6061 offset pivot. Offsetting the axial pivot of the upper control arm away from the chassis

allows a gain of about +2.0±0.2° of positive camber as displayed in Figure 5 (8).

Figure 5 – Ayotte Technologies Offset Bushings

Ayotte Technologies offers this product as both a part and a service. The customer can

send their upper control arms to them, where they will then replace the existing rubber

bushings with the new non-compliant offset bearings. They also offer just the parts, but it is

noted that this is not intended to be a do it yourself kit, a shop that can press out the original

pivots would be required; installation of the new parts requires specially designed tools.

Ayotte Technologies stopped manufacturing this camber correction kit in 2009. Due to

the poor economy and low sales, Thom could just not feasibly justify making only a couple

parts and selling them in such low volumes.

Hardrace is an aftermarket company that specializes in manufacturing replacement

parts that allow for increased adjustment.


8

HARDRACE PILLOWBALL REAR UPPER ADJUSTABLE CONTROL ARMS

Hardrace was founded in 1998. Hardrace specializes in manufacturing reinforced

suspension products for street and race applications. From hardened rubber bushings, to

pillow ball bushings, Hardrace offer a variety of suspension components (9).

The product displayed in Figure 6 is a replacement camber correction arm for a 2000-

2009 Honda S2000. This part replaces the factory upper control arm with the new Hardrace

part. Included with this part is a machined control arm, with new bushings and ball joints.

The machined fit slider allows for the ball joint to be positioned at a desired location

for ideal camber adjustment. This sliding ball joint is one very common method of adjusting

the camber angles, and can be found of a variety of makes and brands camber kits.

Figure 6 – Hardrace Honda S2000 Rear Camber Kit

Hardrace’s replacement control arms offer a product that is relatively easier for the

customer to install, as no specialty tools are needed for installation.

Hardrace offers adjustable control arms for a variety of makes and models.


9

HARDRACE REAR ADJUSTABLE LOWER CONTROL ARM

Hardrace was founded in 1998. Hardrace specializes in manufacturing reinforced

suspension products for street and race applications. From hardened rubber bushings, to

pillow ball bushings, Hardrace offer a variety of suspension components (10).

The product displayed in Figure 7 is a replacement lower control arm for a 1989-1994

Nissan S13 and R32 Skyline. This part replaces the factory lower control arm with the new

Hardrace part. Included with this part is a fabricated control arm, with new bushings and

spherical ball joints.

The spherical ball joint allows for adjustment of spindle angles for the desired alignment

values. Although the adjustment is more difficult than a sliding style ball joint, the spherical

ball joint offers a more cost effective method to adjustable alignment.

Figure 7 – Hardrace Nissan 240sx Lower Control Arm

Hardrace’s replacement control arms offer a product that is relatively easier for the

customer to install, as no specialty tools are needed for installation.

Based on the research, ten features from the various types of camber correction stuck

out the most. The next step was to determine the features in order of importance. They were

then labeled as Customer Features and put into a survey to decide the order of importance.


10

CUSTOMER FEEDBACK, FEATURES AND OBJECTIVES

SURVEY ANALYSIS The ten features that were found to be most important from the research were put into

a survey. The purpose of the survey was to determine the importance of the ten customer

features that would be designed for in the creation of a camber correction control arm for the

Acura NSX. The ratings were listed from 1-5 with 5 being the most important. It also asked

how much they would be willing to pay for such a product by choosing a dollar amount

range. The survey was posted on the NSX web forum http:// http://www.nsxprime.com in

which there was 15 responses. The results were analyzed and Table 1 shows the importance

of each feature varied. Replaceable Wear Items had the highest importance at 12%, while the

Ease of Installation had the least importance at 7%. The cost of how much customers would

be willing to pay for this product came out to about $1200. (For the complete survey results,

see Appendix B & C)

Table 1 – Survey Results

With the Customer Features defined, Product Objectives were developed as a way to obtain

measurable results.

Customer Features

Customer

Importance

Designer

Multiplier

Customer

Satisfaction

Planned

Satisfaction

Improvement

Ratio

Modified

Importance

Relative

Weight

Relative

Weight %

Safety 5 1 4.40 4.8 1.09 5.45 0.11 11.13%

Reliability 5 1 4.60 4.8 1.04 5.22 0.11 10.64%

Durability 5 1 4.40 4.8 1.09 5.45 0.11 11.13%

Ease of Maintenance 4.4 1 4.40 4.8 1.09 4.80 0.10 9.79%

Quiet 4.4 1 4.40 4.6 1.05 4.60 0.09 9.38%

Ease of Adjustment 4.2 1 3.60 4.2 1.17 4.90 0.10 10.00%

Replaceable Wear Items 4.75 1.1 3.60 4.6 1.28 6.68 0.14 13.62%

Affordability 3.4 1 3.00 3.6 1.20 4.08 0.08 8.32%

Ease of Installation 2.8 1 3.00 3.6 1.20 3.36 0.07 6.85%

Options of the Product 2.8 1.1 2.20 3.2 1.45 4.48 0.09 9.14%


11

PRODUCT FEATURES AND OBJECTIVES The Product Features are the same as the customer features rated on the survey. They

are listed in order of most to least important in accordance with the survey. Under each

feature are Product Objectives. Product Objectives are goals in which to meet the customer

features. The customer features obtained were translated into measurable variables to

determine if the Project Objectives were met. (See Appendix D for complete Product

Objectives.)

1. Replaceable Wear Items (14%)

a. Replacement bushings and ball joints will be offered as wear components

2. Safety (11%)

a. An appropriate factor of safety in the design.

b. The safety factor will exceed any shock stresses the control arm may

encounter.

3. Reliability (11%)

a. The mechanical assembly will follow a list of allowable torques for all

fasteners included with the finished product.

b. Industry Hardware standards (of similar applications) will be used to

determine hardware selection.

4. Durability (11%)

a. The material selection of the new control arm will be rust resistant.

b. The control arm will also be powder coated to resist corrosion.

c. The included bushings and ball joints will meet or exceed the specifications of

the original equipment on the vehicle.

5. Ease of Maintenance (10%)

a. Visibility of all inspection items will be in plain sight when on an automotive

service lift. (removal of no parts for inspection will be required)

b. Maintenance will include routine inspection of bushings and ball joints for

damage or wear. (same as factory repair manual)

6. Ease of Adjustment (10%)

a. Each control arm will be able to be adjusted in under ten minutes when on an

alignment lift.

b. Adjustment Hardware will be accessible without the removal of any additional

parts.

i. Standard tools will be used to make adjustments.

7. Quiet (9%)

a. Measurement (with decibel meter) will be performed both before and after

installation of the new control arm under the same test conditions.

i. The street kit will not add any additional noise to the vehicle when


12

compared to the original control arm.

ii. The race kit may add additional noise to the ride of the vehicle when


8. Options of product (10%)

a. The product will be offered in two different kits.

i. Street (compliance) kit utilizing bushings that allow normal flexibility.

(Rubber, Polyurethane, etc)

ii. Race (non-compliance) kit utilizing bushings that do not allow

flexibility (delrin).

1.Material properties will determine bushing selection.

9. Affordability (8%)

a. The complete set of (2) upper control arms with all included brackets,

bushings, ball joints and hardware will not exceed $1200 to purchase.

10. Ease of Installation (7%)

a. The total installation time for a qualified mechanic with the standard tools

should be no more than four hours.

After coming up with the Product Objectives, the next step was to analyze the importance of

each.


13

ENGINEERING CHARACTERISTICS The product objectives were then put into a Quality Function Deployment labeled as

Engineering Characteristics and were cross referenced with all the Product Features and

weights to determine how important each was to the entire design. They are listed in Table 2

by percentage in the order of higher importance to lower with OEM specified bushings and

ball joints having the most importance and Standard Tools having the least importance.

Table 2 – Engineering Characteristics

Engineering Characteristic Importance %

OEM Spec. Bushings/Ball Joints 14%

Material 12%

Replaceable Standard Parts 11%

Hardware Torques 10%

Standard Hardware 8%

Product Variations Offered 8%

Installation Time 7%

Adjustment Time 7%

Design Safety Factor 6%

Maintenance - Service Manual 6%

Interior Decibel Test 5%

Standard Tools Used 5%

After the importance of each Product Objective and Engineering Characteristic were

realized, Concepts could then be developed.


14

CONCEPT GENERATION AND SELECTION

STANDARD BUSHING SELECTION

Replaceable wear items were the most important

feature in a new control arm from the results of the

customer survey due to the lack of replacement parts in

the factory control arms. Energy Suspension

Components offers a variety of OEM specification

polyurethane bushings that can be easily installed or

removed from a bushing housing. Part Number

16.3104G bushings met the dimensions of the space in

the NSX sub-frame, and would be used in the design

of each concept below. Figure 8 depicts the Energy

Suspension bushings that will be used.

UNIVERSAL BALL JOINT SELECTION

In addition to replacement bushings, ball joints

are the other feature that exists as a wear item in

control arm design. The factory control arm does not

offer a replacement ball joint so the entire arm must

be replaced in the event of a failure. Initial

investigation led me to target an OEM replacement

ball joint, but finding the dimensions to match the hub

insert proved impossible. Universal Ball Joint or Rod

Ends as seen in Figure 9 have commonly been found

in race car suspension. QA1 offers Chromalloy rod

ends in a variety of sizes that offer high strength

characteristics and flexibility in terms of swivel

motion. A 5/8-18 rod end will be used in the design of

the control arm, and mating to the hub is accomplished

with standard hardware.

Figure 8 - Energy Suspension

16.3104G Bushings

Figure 9 - QA1 Chromalloy XMR

Series Rod End


15

RELOCATED AXIS MOUNTING BRACKET

The first concept shown in Figure 10 will be

referred to as the Relocated Axis Mounting Bracket.

The factory control arms utilize mounting brackets that

are molded into the rubber bushings and fixed into the

control arms. To accommodate a standard bushing,

initial thoughts included relocating the rotation axis to

allow through bolt and nut fastening. The complexity

and costs associated with this design proved that it

would not be feasible, along with the changes in the

suspension geometry associated with relocating the

rotational axis.

2 PIECE SHOULDER MOUNTING BRACKET

The second and selected concept for

mounting the control arms to the chassis was

based around the factory molded bracket. It

utilizes a 2 piece design that threads together

through the bushing. It is then mounted to the

chassis using the factory bolts and torque

specifications. This design allows the use of the

Energy Suspension bushings, and retains the

factory location for control arm rotation. The

shoulders on each side of the bushing will

prevent longitudinal movement of the control

arm.

BILLET SLIDING-ADJUSTABLE ARM

Initial thoughts for control arm design followed similar to other adjustable camber arms

on the market. Billet construction, welded joints, and a locking slider mechanism to

physically adjust the length of the arm. Several factors proved this option to be not feasible

such as cost to manufacture, space confinements and complex angles. Alternative options

were then explored.

Figure 10 – Relocated Axis

Mounting Bracket

Figure 11 – 2 Piece Shoulder Mounting

Bracket


16

TUBULAR FIXED LENGTH ARM

Tubular Steel was selected to be the material of choice as it is relatively cheap, easy to

weld, and very strong. This approach utilizes a fixed camber correction in the overall length

of the arm. The camber adjustment will still be retained in the factory lower control arm

mounting point for fine tuning alignment values through the use of the cam bolt. The key

mounting points were first modeled and then connected with a structure of supports. The bent

section utilizes a standard three inch center line radius bend that met the available resources

for tube construction. The selected tubing is 4130 Chromalloy Steel with a 1” outer diameter

and a 0.120” wall thickness. The design in Figure 12 below is the selected design, as from a

cost and feasibility standpoint it met all the requirements set forth.

Figure 12 – Fixed Length Camber Correction Arm

Figure 13 – Selected Components in Assembly


17

CALCULATIONS

CALCULATING THE FORCES IN THE CONTROL ARM

Force calculation began by estimating the heaviest corner weight of an Acura NSX.

This was achieved by finding the heaviest model; an automatic transmission, targa top NSX

which has a curb weight of 3,204 lbs. This was then rounded to 3,500 lbs for a design weight.

The weight distribution front to rear for the NSX is approximately 42/58.

𝑅𝑒𝑎𝑟 𝐶𝑜𝑟𝑛𝑒𝑟 𝑊𝑒𝑖𝑔𝑕𝑡 = 𝑅𝑒𝑎𝑟 𝑊𝑒𝑖𝑔𝑕𝑡 𝐷𝑖𝑠𝑡𝑟𝑖𝑏𝑢𝑡𝑖𝑜𝑛 ∗ 𝐷𝑒𝑠𝑖𝑔𝑛 𝑊𝑒𝑖𝑔𝑕𝑡

2

𝑅𝑒𝑎𝑟 𝐶𝑜𝑟𝑛𝑒𝑟 𝑊𝑒𝑖𝑔𝑕𝑡 = 0.58 ∗ 3500𝑙𝑏𝑠

2= 1,015 𝑙𝑏𝑠

Controls arms see the most loads during cornering. In an extreme cornering situation

with high traction tires and high speeds, I anticipate the max acceleration in a corner to be

2g-forces. The 3,500lb design weight is equal to 1,587.57kg. The equations below break

down the acceleration force for the whole vehicle, and then for the rear corner.

𝐹 = 𝑣𝑒𝑕𝑖𝑐𝑙𝑒 𝑚𝑎𝑠𝑠 ∗ 2 𝑔

𝐹 = 1587.57𝑘𝑔 ∗ 2 9.8𝑚

𝑠2 = 31,116.37 𝑁

𝑅𝑒𝑎𝑟 𝐶𝑜𝑟𝑛𝑒𝑟 𝐹𝑜𝑟𝑐𝑒 = 𝑅𝑒𝑎𝑟 𝑊𝑒𝑖𝑔𝑕𝑡 𝐷𝑖𝑠𝑡𝑟𝑖𝑏𝑢𝑡𝑖𝑜𝑛 ∗ 𝐿𝑎𝑡𝑒𝑟𝑎𝑙 𝐹𝑜𝑟𝑐𝑒

2

𝑅𝑒𝑎𝑟 𝐶𝑜𝑟𝑛𝑒𝑟 𝐹𝑜𝑟𝑐𝑒 = 0.58 ∗ 31,116.37 𝑁

2= 9,023.75 𝑁 𝑜𝑟 2,028.62 𝑙𝑏𝑓


18

FREE BODY DIAGRAM

Dimensions were then pulled from the vehicle to model a free body diagram of the rear

suspension components as seen in the Figure below. In this particular situation, the upper

control arm will experience a compressive load of 2,225.6 lbf, which will be used in the

testing of this control arm. The control arms were pinned at the body mounting points and

break down as follows.

BD: Upper Control Arm

AC: Lower Control Arm

BA: Knuckle

FE: Hub/Spindle

FG: Wheel/Tire

F2: Shock Absorber

F1: Corner Weight

F3: Cornering Force

Figure 14 – Free Body Diagram 1

Table 3 – Compressive Force Components

Equations Results

∑M = 0 => 0.732 × RD17[Y] + 0.164 × RD17[X] = 0

∑F[X] = 0 => RB17[X] + RD17[X] = 0

∑F[Y] = 0 => RB17[Y] + RD17[Y] = 0

∑F[X] = 0 => RD[X] − RD17[X] = 0

∑F[Y] = 0 => RD[Y] − RD17[Y] = 0

RB17[X] = 2171.467 lb

RB17[Y] = −488.002 lb

RD17[X] = −2171.467 lb

RD17[Y] = 488.002 lb


19

The cornering load was then reversed to simulate a turn in the same conditions but

opposite direction. With everything else staying the same, the upper control arm now is

under tension with a 683.6lb tensile force as displayed in the Figure below.

Figure 15 – Free Body Diagram 2

Table 4 – Tensile Force Components

Equations Results

∑M = 0 => 0.732 × RD17[Y] + 0.164 × RD17[X] = 0

∑F[X] = 0 => RB17[X] + RD17[X] = 0

∑F[Y] = 0 => RB17[Y] + RD17[Y] = 0

∑F[X] = 0 => RD[X] − RD17[X] = 0

∑F[Y] = 0 => RD[Y] − RD17[Y] = 0

RB17[X] = −666.952 lb

RB17[Y] = 149.887 lb

RD17[X] = 666.952 lb

RD17[Y] = −149.887


20

FABRICATION AND ASSEMBLY

MANUFACTURING PROCESSES

The fabrication process began by

bending the 90° angles in the tubing.

This was accomplished using an air over

hydraulic JD squared tubing bender with

the correct bending die for the 1” OD

tubing. The key framework to each

control arm was then saw-cut to a rough

length on a band saw.

Figure 16 – Mandrel Bent and Saw Cut Parts

The rod end sleeves were then turned on

a lathe from 4130 1” OD round bar

stock. A hole was drilled and tapped to

accommodate the 5/8-18 threads on the

rod end. The knuckle inserts were then

turned on a lathe, ensuring that

tolerances remained tight for a press fit

in the knuckle. Safety Washers and

forged hardware was then fitted to

verify all holes fit accordingly.

Figure 17 – Turned Sleeves and Inserts


21

Appropriate sized 4130 tubing was

sourced to closely match the needed

dimensions for the bushing housings.

The OD was then turned and faced on a

lathe to meet the needed dimensions.

The ID bore was a near perfect fit from

the supplier, and only required a light

honing to provide a smooth finish for the

bushing to rest against.

Figure 18 – Turned and Honed Bushing Housing

All tubing joints were then carefully

notched to provide excellent joint

fitment before welding. A lathe was

used to accomplish all tube notching.

The compound tool post securely held

each part. The desired angle could then

be set, and a milling bit could do the

cutting.

Figure 19 – Radius Notched Joint


22

Each part was carefully shaped in the

methods mentioned above, and slowly

came together to create the outline of

the control arm. An alignment bar was

fabricated to ensure that each of the

bushing sleeves remained in alignment

during fit up and tack welding.

Figure 20 – Alignment Bar

Next the mounting brackets were turned

on a lathe to meet the dimensions

needed for the pre milling preparation.

They were then drilled and tapped to

accept the ½-20 threaded rod for

assembly through the bushings.

Figure 21 – Turned Mounting Brackets

The mounting brackets were then sent to a

machine shop for the final stage of

machining. They were CNC milled to have

the radius along with the elongated holes

cut in. These parts would then accept the

mounting hardware to secure the arms to

the chassis.

Figure 22 – CNC Milled Mounting Brackets


23

As each component came together, tack

welds were used to hold the components

to each other. This allowed initial test

fitting to occur on the vehicle to verify

that all designed dimensions had

matched the actual components.

Figure 23 – Tack Welded Joints

The tacked together control arms were

then sent to a competent welder where

each joint was fully TIG welded using

ER70S2 filler rod. An alignment bar

was used during welding to ensure that

no warping or twisting had occurred as

a result of the heat.

Figure 24 – Complete GTAW Joint Detail


24

The completely welded control arms

were once again assembled and tested

for fit up. It was at this point that the

control arm was ready for load testing,

which can be viewed in the next

section of this report.

Figure 25 – Complete GTAW Welded Control Arm

CORROSION RESISTANCE

After testing was complete on each

control arm, they were media blasted

to remove any contaminants on the

surface. They were further cleaned

and then powder coated. After

curing at 400° F for approximately

12 minutes, the parts were allowed to

cool where the finish would finally

cure.

Figure 26 – Powder Coated Finish


25

FINAL ASSEMBLY

After completion of all machining, testing, and corrosion processes, the control arms

were ready for final assembly and installation. Assembly consisted of simply threading in the

rod end, pressing in the bushings, and threading together the mounting brackets through the

bushings. The control arm is then fastened to the chassis utilizing the 4 factory bolts and

torqued to the values listed in the factory service manual. The taper insert could then be

started into the knuckle, and the bolt dropped through each component in the rod end. As this

bolt was tightened, the knuckle insert was pressed into the knuckle until seated and torqued

accordingly.

Figure 27 – Installed Component


26

TESTING

TESTING PROCESS

To test the integrity of the fabricated control arms,

along with a comparison to the model developed in

Solidworks, a hydraulic press was used to apply

load to the control arms. A jig was fabricated to fix

the bushing housings of the control arms to the base

of the press. The ram was then fixed to the control

arm through the rod end. The load was applied as a

compressive load, and to be tested to the values

calculated from the free body diagram.

Figure 28 – Testing Jig

A dial indicator was placed under the rod end and

used to measure the deflection of the control arm at

each increment of load. The control arms were

loaded to 2,270 lbs of compressive force, and the

results can be analyzed on the next page.

Figure 29 – Deflection Measurement


27

TESTING RESULTS

The data recorded in Table 5 is the raw data pulled from the physical testing of the

control arms. The Estimated Displacement values come from a Solidworks Simulation model

of the control arm with the same force applied.

Table 5 – Testing Data

The graphical results are depicted in the Figure below. The Red and Black lines on the

graph depict the actual deflection values recorded during the physical testing. The nearly

hidden blue line is the estimated deflection from the Solidworks Simulation. The purple

horizontal line represents the maximum safe deflection before the material will begin to

exceed its yield strength. With a safety factor of 2.0 the 5/8-18 fastener securing the rod end

to the control arm will exceed its yield strength at loads in excess of 6900lbs. The Maximum

Safe Deflection is derived from the Solidworks Simulation based on the deflection value

estimated at a 6900lb load. At the expected and tested loads, our deflection remained well

beneath the maximum safe deflection, which confirms the integrity and safety of these

control arms.

Figure 30 – Testing Results

0.0000

0.0100

0.0200

0.0300

0.0400

0.0500

0.0600

0 500 1000 1500 2000 2500

Dis

pla

cem

ent

(in

)

Load (lbs)

Force vs. Displacement

Estimated Displacement

(in)Control Arm 1

Control Arm 2


28

SCHEDULE AND BUDGET

SCHEDULE The schedule measures 30 weeks long. It starts with the Content Review phase on

September 29th

and ends with the Final Project Report on April 23rd

. The figure below shows

the scheduling of designing, modeling, ordering, fabricating, assembling and testing. (For the

complete schedule, see Appendix E.)

Figure 31 – Schedule Overview

BUDGET The budget is the list of all planned expenses involved with the project. The total cost

of two replacement upper control arms was estimated to cost around $1400. The actual costs

totaled just over $560. The reason for the large cost difference can be associated with the

initial plans for billet construction and machining costs versus the actual tubular construction.

In addition to the sponsorship of CNC milling, the time and labor costs for metal working are

not accounted for, as previously available equipment and tooling was used. (For the

complete Budget, see Appendix F)

Table 6 – Budget

Component Vendor/Supplier Estimated Cost Actual Cost

4x Bushings Energy Suspension $100 $30.99

2x Ball Joints Summit Racing $100 $67.70

2x Mounting Brackets McMaster Carr $150 $321.47

2x Control Arms McMaster Carr $200 ^

Machining Costs Faxon Firearms $500 Sponsor

Hardware McMaster Carr $50 $16.33

Welding & Tube Bending Dave Hentz $100 $100

Powder Coating PowderBuyThePound $0 $25

TOTAL $1,200 $561.49


29

CONCLUSION

While camber correction is certainly not an innovative product in itself, the components

and application of this specific control arm do have some originality. In retrospect there are

only a very few attributes that I would like to make change points, but from an initial

prototype standpoint, I feel that this control arm meets all of the requirements plus some

more. The design of the mounting brackets takes an approach that I have not seen

accomplished before, which I pride the final result of. The final product displayed is unique,

compact, structurally sound, easy to install, easy to maintain and overall entails all of the

requirements set forth by the product objectives.


30

WORKS CITED

1. Wikipedia. [Online] Otober 9, 2013. http://en.wikipedia.org/wiki/Honda_NSX.

2. Urlage, Brian. Cincinnati, September 2, 2013.

3. Nguyen, Andrew. Cincinnati, September 2, 2013.

4. Car Bibles. [Online] [Cited: October 5, 2013.]

http://www.carbibles.com/suspension_bible.html.

5. Discount Tire. [Online] October 5, 2013.

http://www.discounttire.com/dtcs/infoAlignment.dos.

6. Dali Racing. [Online] [Cited: August 27, 2013.] http://daliracing.com/v666-

5/catalog/index_browse_part.cfm?focus=2247.

7. Cedar Ridge Fabrication. [Online] [Cited: August 29, 2013.]

http://www.cedarridgefabrication.com/NSX_Suspension.

8. NSX Prime. [Online] [Cited: September 2, 2013.]

http://www.nsxprime.com/forum/showthread.php/84729-Camber-Correction-

Hardware?highlight=camber+correction+hardware.

9. Hardrace. [Online] [Cited: September 2, 2013.]

http://www.hardrace.com/products.asp?strClass1=11&strClass2=31.

10. Hardrace. [Online] [Cited: September 2, 2013.]

http://www.hardrace.com/products.asp?strClass1=7.

31

APPENDIX A – RESEARCH

Interview with Performance NSX Shop Owner Brian Urlage: 1675 Ohio 28

Goshen, Ohio 45122

Brian Urlage has 21 years of experience in the car industry.

He opened Source1 Automotive in 2006, where they are now known

nation-wide as a leader in Performance NSX modification and

maintenance.

Brian notes that the aftermarket support for the NSX is substantially

less than many other often modified automobiles.

Brian sees camber issues often, as there is no cost effective way to

manage this issue on customer’s vehicles. Brian notes that being able to

manage camber issues for customer will improve tire wear for

customers that simply want to drive their cars, along with improving

traction in straight line racing and light turns.

He sees there being a high demand for this product if quality and ease

of adjustment is there. He stated that NSX owners do not mind paying

for a quality product that allows for ease of installation and improves

troublesome issues such as camber.

Brian has faith in my skills as he has seen the quality of work I have

produced on other projects and is excited to see where I can take this

project.

Interview with Acura NSX Builder Andrew Nguyen: 5656 Cheviot Road

Cincinnati, Ohio 45247

Andrew Nguyen has been building cars for 14 years.

Andrew enjoys the exterior of the NSX the most, as he feels it was so

ahead of its time appearance-wise.

Andrew feels there is a solid aftermarket support, as modifying these

vehicles has become more common as companies have taken up many

challenges to meet customer’s needs.

He would like to see camber adjustment that allows for running wider

wheel/tire combinations with the best contact patch. Also for quick

adjustment depending on the type of driving or racing he is taking part

in.

He prefers sliding style ball joint’s as they offer quick and easy

adjustment of camber.

Cost of parts is not an issue to Andrew, as he is most concerned about

durability and ease of adjustment.

Andrew is excited to see the finished product; along with all the stages

leading up to it, he plans to be my first customer.

32

Dali Racing Non-Compliance Rear Beam

Dali Racing offers a service to correct rear camber for customers.

They require the rear beam of the customer’s NSX to be sent to

them, where they will then replace it with a Non-Compliance

Rear Beam. They offer two levels of camber correction,

depending on what the customer wants.

The Non-Compliance Rear Beam involves removing the

customer’s original rubber bushings, and replacing them with

solid Aluminum components with an offset center hole. This

allows the original alignment cam bolt to be utilized for fine

tuning of the camber.

Dali Racing does not recommend use of this camber correction

for street use, as it replaces one compliant aspect of the

suspension with a non-compliance part.

This Product:

Eliminates the possibility of Dynamic camber settings

Should be used with Non-Compliance Toe Links for best

handling improvement

Is Sold Exchange Only in Our Shop – Requires

Modification of the Rear Beam

$700.00 USD

Offered only as a

service, so there is a gap

of downtime for the

customer.

Still requires customer

to remove and ship out

their rear beam. Along

with installation upon

receiving the modified

beam.

Not recommended for

street use.

Requires permanent

modification to the rear

beam.

Less than ideal customer

service.

http://daliracing.com/v666-

5/catalog/index_browse_part.cfm?focus=2247

8/27/2013

33

Cedar Ridge Fabrication (TitaniumDave) Rear Beam Bearings

Cedar Ridge Fabrication also offers Rear Beam Bearings. Similar to

Dali Racing, these bearings and sleeves replace the original rubber

bushings in the rear beam of the NSX. They utilize an offset center

hole, to allow more camber adjustment at the factory alignment cam

bolt.

They offer the components separately, or as a service depending on

the customer’s needs. Cedar Ridge Fabrication also offers

complementing components to the Rear Beam Bearings. They

include the following: Front Lower Bearings, Rear Upper A-Arm

Bearings and Rigid Toe Links.

Utilizing Cedar Ridge’s entire selection of suspension components

makes for a solid non-compliance rear suspension. All of the

original rubber bushings are replaced with solid non-compliance

parts. This is ideal for a strictly race car, as the dynamic alignment

settings will vary only by ride height and not by rubber bushing

deformation.

$480.00 USD (two

locations)

Installation required

for these rear beam

bearings is extremely

involved, and cannot

be done by an average

car enthusiast.

Complete non-

compliance camber

correction (four

locations) costs

$880.00 and still need

to be installed by the

customer.

Complete non-

compliance kit (twelve

locations) costs

$3600.00 USD

installed into the

customer’s NSX.

Requires permanent

modification to the

rear beam.

High quality product,

high cost, not

recommended for most

street driven cars.

http://www.cedarridgefabrication.com/NSX_Suspension

8/29/2013

34

Ayotte Technologies (Thom) Offset Upper Control Arm

Bushings

Ayotte Technologies takes a slightly different approach than the

aforementioned companies. They correct camber by replacing the

rear upper control arm’s axial compliant bushings with non-

compliant self lubricating polymer bearing material mated to a

billet T6-6061 offset pivot. Offsetting the axial pivot of the upper

control arm away from the chassis allows a gain of about

+2.0±0.2° of positive camber.

Ayotte Technologies offers this product as both a part and a

service. The customer can send their upper control arms to them,

where they will then replace the existing rubber bushings with the

new non-compliant offset bearings. They also offer just the parts,

but it is noted that this is not intended to be a do it yourself kit, a

shop that can press out the original pivots would be required;

installation of the new parts requires specially designed tools.

Ayotte Technologies stopped manufacturing this camber

correction kit in 2009. Due to the poor economy and low sales,

Thom could just not feasibly justify making only a couple parts

and selling them in such low volumes.

$450.00 USD

Installation required

offset control arm

bearings is extremely

involved, and cannot be

done by an average car

enthusiast.

Reuses the non-

replaceable original ball

joints.

Known to squeak and

make noise and need

often lubrication.

Requires permanent

modification to the

upper control arms.

They are no longer

manufactured.

http://www.nsxprime.com/forum/showthread.php/84729-

Camber-Correction-

Hardware?highlight=camber+correction+hardware

9/2/13

35

Hardrace Pillowball Rear Upper Adjustable Control Arms

(00-09 Honda S2000)

Hardrace was founded in 1998. Hardrace specializes in

manufacturing reinforced suspension products for street and race

applications. From hardened rubber bushings, to pillow ball

bushings, Hardrace offer a variety of suspension components.

The product displayed above is a replacement camber correction

arm for a 2000-2009 Honda S2000. This part replaces the factory

upper control arm with the new Hardrace part. Included with this

part is a machined control arm, with new bushings and ball joints.

The machined fit slider allows for the ball joint to be positioned at

a desired location for ideal camber adjustment. This sliding ball

joint is one very common method of adjusting the camber angles,

and can be found of a variety of makes and brands camber kits.

Hardrace’s replacement control arms offer a product that is

relatively easier for the customer to install, as no specialty tools

are needed for installation.

$535.00 USD

Offers a cost effective

method to replace and

adjust camber.

Includes new bushings

and ball joints.

Relatively easy

installation.

Priced well for a quality

product.

Not offered for the

Acura NSX.

http://www.hardrace.com/products.asp?strClass1=11&strCla

ss2=31

9/2/13

36

Hardrace Rear Adjustable Lower Control Arm (Nissan S13

and R32 Skyline)

Hardrace was founded in 1998. Hardrace specializes in

manufacturing reinforced suspension products for street and race

applications. From hardened rubber bushings, to pillow ball

bushings, Hardrace offer a variety of suspension components.

The product displayed above is a replacement lower control arm

for a 1989-1994 Nissan S13 and R32 Skyline. This part replaces

the factory lower control arm with the new Hardrace part.

Included with this part is a fabricated control arm, with new

bushings and spherical ball joints.

The spherical ball joint allows for adjustment of spindle angles

for the desired alignment values. Although the adjustment is more

difficult than a sliding style ball joint, the spherical ball joint

offers a more cost effective method to adjustable alignment.

Hardrace’s replacement control arms offer a product that is

relatively easier for the customer to install, as no specialty tools

are needed for installation.

$449.00 USD

Offers a cost effective

method to replace and

adjust alignment angles.

Includes new bushings

and spherical ball joints.

Relatively easy

installation.

Priced well for a quality

product.

Not offered for the

Acura NSX.

http://www.hardrace.com/products.asp?strClass1=7

9/2/13

37

APPENDIX B – CUSTOMER SURVEY

The purpose of this survey is to evaluate what features are most important in the design of a new

rear camber kit for Acura NSX’s. This information will also be used to evaluate how satisfied

customers are with the current options available for NSX rear camber correction.

How important is each feature to you for the design of a new NSX Rear Camber Kit?

Please circle the appropriate answer. 1 = low importance 5 = high importance

Average

Easy to Install 1(1) 2(1) 3(2) 4 5(2) N/A 3.17

Easy to Maintain 1 2 3(1) 4(1) 5(4) N/A 4.50

Safe 1 2 3 4 5(6) N/A 5.00

Reliable 1 2 3 4 5(6) N/A 5.00

Durable 1 2 3 4 5(6) N/A 5.00

Easy to Adjust 1 2 3(2) 4(2) 5(2) N/A 4.00

Quiet 1 2 3(1) 4(1) 5(4) N/A 4.50

Affordable 1 2(1) 3(2) 4(1) 5(2) N/A 3.67

Replaceable Wear Items 1 2 3 4(1) 5(4) N/A(1) 4.80

Options 1(2) 2(1) 3(2) 4 5(1) N/A 2.50

How satisfied are you with the current options for NSX Rear Camber Correction?

Please circle the appropriate answer. 1 = very UNsatisfied 5 = very satisfied

Average

Easy to Install 1(1) 2(2) 3(2) 4 5(1) N/A 2.67

Easy to Maintain 1 2(1) 3 4 5(5) N/A 4.50

Safe 1 2(1) 3 4 5(5) N/A 4.50

Reliable 1 2 3(2) 4 5(4) N/A 4.33

Durable 1 2(1) 3(1) 4 5(4) N/A 4.17

Easy to Adjust 1(1) 2(1) 3(1) 4 5(3) N/A 3.50

Quiet 1 2(2) 3 4 5(4) N/A 4.00

Affordable 1(1) 2(3) 3 4 5(2) N/A 2.83

Replaceable Wear Items 1 2(1) 3(3) 4 5(2) N/A 3.50

Options 1(3) 2 3(2) 4 5(1) N/A 2.33

How much would you be willing to spend on this product?

$50-$100 $100-$200 $200-$500(1) $500-$1000(3) $1000-$2000(2)

38

APPENDIX C – QUALITY FUNCTION DEPLOYMENT (QFD)

De

sig

n S

afe

ty F

acto

r

Ha

rdw

are

To

rque

s

Sta

nd

ard

Hard

wa

re

Mate

ria

l

OE

M s

pec.

bu

sh

ings/b

all

join

ts

Main

ten

an

ce

Fo

llow

s F

acto

ry R

epa

ir M

an

ua

l

Inte

rior

De

cib

el T

est

Ad

justm

en

t T

ime

Sta

nd

ard

To

ols

Use

d

Re

pla

ca

ble

Sta

nd

ard

Pa

rts

Insta

llatio

n T

ime

Typ

es o

f P

rodu

cts

ava

ilable

Cu

sto

me

r im

po

rta

nce

De

sig

ne

r's M

ultip

lier

Cu

rre

nt

Sa

tisfa

ctio

n

Pla

nn

ed

Sa

tisfa

ctio

n

Impro

ve

me

nt

ratio

Mod

ifie

d I

mp

ort

ance

Re

lative

weig

ht

Re

lative

weig

ht

%

Safety 9 3 3 3 5 1 4.4 4.8 1.1 5.5 0.11 11%

Reliability 9 3 3 3 5 1 4.6 4.8 1.0 5.2 0.11 11%

Durability 9 3 5 1 4.4 4.8 1.1 5.5 0.11 11%

Ease of Maintenance 1 3 3 9 3 3 4.4 1 4.4 4.8 1.1 4.8 0.10 10%

Quiet 3 9 4.4 1 4.4 4.6 1.0 4.6 0.09 9%

Ease of Adjustment 1 3 9 3 3 4.2 1 3.6 4.2 1.2 4.9 0.10 10%

Replaceable Wear Items 3 1 9 3 4.8 1.1 3.6 4.6 1.3 6.7 0.14 14%

Affordability 3 3 3 3 3 3.4 1 3 3.6 1.2 4.1 0.08 8%

Ease of Installation 3 3 3 3 9 2.8 1 3 3.6 1.2 3.4 0.07 7%

Options of the Product 1 9 2.8 1.1 2.2 3.2 1.5 4.5 0.09 9%

Abs. importance 1.00 1.70 1.37 1.90 2.31 1.02 0.84 1.11 0.80 1.77 1.17 1.23 16.2 49.0 1.0 1.0

Rel. importance 0.06 0.10 0.08 0.12 0.14 0.06 0.05 0.07 0.05 0.11 0.07 0.08 1.0

Mitchell BackscheiderAcura NSX Camber Correction9 = Strong3 = Moderate1 = Weak

39

APPENDIX D – PRODUCT OBJECTIVES

Based on the survey, the project objectives are the list of customer features that are taken into

consideration during the design phase of my product. The following is a list of product objectives

and how they will be obtained or measured to ensure that the goal of the project is met.

1. Replaceable Wear Items (14%)

a. Replacement bushings and ball joints will be offered as wear components

2. Safety (11%)

a. An appropriate factor of safety in the design.

b. The safety factor will exceed any shock stresses the control arm may encounter.

3. Reliability (11%)

a. The mechanical assembly will follow a list of allowable torques for all fasteners

included with the finished product.

b. Industry Hardware standards (of similar applications) will be used to determine

hardware selection.

4. Durability (11%)

a. The material selection of the new control arm will be rust resistant.

b. The control arm will also be powder coated to resist corrosion.

c. The included bushings and ball joints will meet or exceed the specifications of the

original equipment on the vehicle.

5. Ease of Maintenance (10%)

a. Visibility of all inspection items will be in plain sight when on an automotive service

lift. (removal of no parts for inspection will be required)

b. Maintenance will include routine inspection of bushings and ball joints for damage

or wear. (same as factory repair manual)

6. Ease of Adjustment (10%)

a. Each control arm will be able to be adjusted in under ten minutes when on an

alignment lift.

b. Adjustment Hardware will be accessible without the removal of any additional parts.

i. Standard tools will be used to make adjustments.

7. Quiet (9%)

a. Measurement (with decibel meter) will be performed both before and after

installation of the new control arm under the same test conditions.

i. The street kit will not add any additional noise to the vehicle when


ii. The race kit may add additional noise to the ride of the vehicle when


40

8. Options of product (10%)

a. The product will be offered in two different kits.

i. Street (compliance) kit utilizing bushings that allow normal flexibility.

(Rubber, Polyurethane, etc)

ii. Race (non-compliance) kit utilizing bushings that do not allow flexibility

(delrin).

2.Material properties will determine bushing selection.

9. Affordability (8%)

a. The complete set of (2) upper control arms with all included brackets, bushings, ball

joints and hardware will not exceed $1200 to purchase.

10. Ease of Installation (7%)

a. The total installation time for a qualified mechanic with the standard tools should be

no more than four hours.

41

APPENDIX E – SCHEDULE

TASKS Sep

29

-Oct

5

Oct

6 -

12

Oct

13

- 1

9

Oct

20

- 2

6

Oct

27

- N

ov

2

No

v 3

- N

ov

9

No

v 1

0 -

16

No

v 1

7 -

23

No

v 2

4 -

30

Dec

1 -

7

Dec

8 -

14

Dec

15

- 2

1

Dec

22

- 2

8

Dec

29

- J

an 4

Jan

5-

Jan

11

Jan

12

- 1

8

Jan

19

- 2

5

Jan

26

- F

eb 1

Feb

2 -

8

Feb

9 -

15

Feb

16

- 2

2

Feb

23

- M

ar 1

Mar

2 -

8

Mar

9 -

15

Mar

16

- 2

2

Mar

23

- 2

9

Mar

30

- A

pr

5

Ap

r 6

- 1

2

Ap

r 1

3-

19

Ap

r 2

0 -

26

Content review (advisor) 9

Proof of Design Agree (advisor) 16

Concepts/Selection (advisor) 16

3D Model - (Mounting Brackets) 23

3D Model - (A-Arm Part 1) 6

3D Model - (A-Arm Part 2) 20

Design Calculations 4

Design Freeze 14

Bill of Materials 8

Shop Drawings 15

Order Parts and Materials 15

Presentation to Faculty 31

Design report to Advisor 7

Fabrication 26

Assembly 26

Testing 5

Modification 5

Final Testing 12

Demonstration to Advisor 28

Tech Expo 3

Presentation to Faculty 17

Advisor final review 18

Due in Library as PDF 23

42

APPENDIX F – BUDGET

Component Vendor/Supplier Estimated Cost Actual Cost

4x Bushings Energy Suspension $100 $30.99

2x Ball Joints Summit Racing $100 $67.70

2x Mounting Brackets McMaster Carr $150 $321.47

2x Control Arms McMaster Carr $200 ^

Machining Costs Faxon Firearms $500 Sponsor

Hardware McMaster Carr $50 $16.33

Welding & Tube Bending Dave Hentz $100 $100

Powder Coating PowderBuyThePound $0 $25

TOTAL $1,200 $561.49

43

APPENDIX G – DETAIL DRAWINGS

rear camber correction for 1991-2005 acura nsx

Documents