modified setup

ASPHALT MODIFIED (Standard 3 Point and 4-Link Cars)

2006 Set-Up and Technical Guide

Phone: (585) 352-5590 • Fax: (585) 352-5593 130 Buell Road • Rochester, NY 14624 Asphalt Modified Set-Up & Technical Guide

w w w.troyerracecars.com

C Copyright 2005 Troyer Inc.

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STEP BY STEP CHASSIS SETUP...

FRONT SUSPENSION 1.

Disconnect stabilizer bar.

2.

Set air pressure & stagger using hot air pressures.

3.

Check fluids.

A. 10 Gallons of fuel.

B. Check radiator fluid, gear oil, engine oil, power steering fluid, etc.

4.

Set frame heights with driver in car or equivalent weight.

A. LF: 2 1/8” RF: 2 7/8” LR: 2 1/2” RR: 3 1/4”

5.

Square rear end & locate left to right.

6.

Set camber.

Recommended camber starting point: o Right Front: -3 o Left Front: +2 How will you decide if this is correct or incorrect for you? a. Tire temperatures. b. Always back up tire temperatures by tire wear. This should be the deciding factor in making a camber change. *NOTE: We do not recommend deviating from these numbers because it will change your bump steer.

7.

Set caster.

Recommended caster starting point: Pinto & Sweet Right Front: +5o Left Front: +2o

*NOTE: We do not recommend deviating from these numbers because it will change your bump steer.

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Asphalt Modified Set-Up & Technical Guide

8.

A-frame angles...

SWEET A. LF Lower: 1.5o up to tire LF Upper: 8o up to tire RF Lower: .5o up to tire RF Upper: 4o up to tire B. Roll center: 4” to left 2 1/4” off ground.

9.

Put car on scales.

PINTO .5o 10o 1o 7o 2 3/4” up 3” left

10. Check total weight.

11. Check left side percentage.

A. Use maximum amount that rules permit.

12. Check rear percentage.

A. Suggested percentage: 52%-53% (Race).

51% (Time Trials).

13. Locate ballast to get desired percentages.

14. Set car to desired amount of wedge.

A. Keep pre-load out of springs. Adjust on all four corners.

B. Suggested percentage: 51% - 53% diagonal or 180-220lbs across rear.

15. Set car back on ground to check ride heights.

16. Put car back on scales to reset wedge if frame heights changed.

17. Center rack alignment and toe setting.

You must center the inner pivot points of the rack with the inner pivot points of the lower a-frames when your front wheels are square to the chassis. a. Remove boots from rack and pinion. b. Turn steering wheel until the inner pivot points of the rack are centered with the inner pivot points of the lower a-frames. c. With someone holding the steering wheel, turn the right front tie rod until the right front wheel is parallel with the right front frame rail. d. Adjust the left front tie rod until you have 3/16” toe out.

Asphalt Modified Set-Up & Technical Guide

C Copyright 2005 Troyer Inc.

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e. Double check by repeating Steps B and C. a. More toe out would help the nose of the car (mostly off throttle). b. Too much toe out could make the car loose on corner entry or create excessive front tire temperatures and tire wear.

18. Ackerman.

A. Ackerman is when your toe out increases as you turn the front wheels left or right. Our cars are built with ackerman in order to give the cars a better nose.

B. Adjustable ackerman is an excellent adjustment and is be coming more and more popular. This is done with an adjust able left front spindle which allows you to shorten the steering arm length. By shortening the left front steering arm, the left front wheel will turn faster than the right front wheel which in turn will increase toe out when turning left.

C. Always reset the toe after changing the ackerman.

D. The difference between toe and ackerman is that more ackerman will not have the drag or friction on the front tires down the straightaways that toe would.

19. Set bump steer.

A. Right Front: .010 to .020 bump out per inch of compression.

B. Left Front: .005 to .010 bump out per inch of extension.

C. The following must be done prior to setting bump steer.

1. Camber 2. Caster 3. Rack centered to lower a-frames 4. Lower a-frames set to same angle as at ride height 5. Remove shocks and springs from front end D. We check bump steer by raising the right front 1” at a time for a total of 3”.

We recommend for the right front approximately .020 bump out per inch. We are primarily concerned with the first two inches. The reason being that an asphalt modified rarely has more than two inches of right front bump.

E. To check the left front, we drop the left front 2” from the right height. We recommend .005 to .010 bump out in this travel. The main concern is that the left front never bumps in.

F. To adjust bump steer: G. On a Pinto or Fairmont type rack, your pivot point is not adjustable. This 4

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Asphalt Modified Set-Up & Technical Guide

H.

leaves all of your adjustment to be done at the spindle. In order to do this, you must replace the factory tie rod end with a heim joint. Then you have to drill the spindle out 5/8�. This will allow you to shim the heim joint to the desired location.

Smart level bumping: Tie rod in relationship to lower a-frame RF: .2o down (tie rod down to tire in relationship to lower a-frame).

LF: 1.2o up (tie rod up to tire in relationship to lower a-frame).

20. Recheck toe.

21. Set brake bias.

A. Suggested percentage: 55%-60% front brake.

22. Hook up stabilizer bar and set neutral.

23. Front anti-roll bar: A. We use a 1 1/8� splined tubular type anti-roll bar. The numbers we use in defining these bars are for reference only. For example;300,350,400,450.

Heavier are also available.

B. A soft anti-roll bar would generally be used on a flatter or tight corner type of race track (like Spencer Speedway). A soft bar allows the car to transfer weight to the right front or off the left rear.

C. A heavier anti-roll bar will make the car tighter on corner entry. You would run a heavier bar on a fast, high banked track such as Thompson or Holland Speedway.

Asphalt Modified Set-Up & Technical Guide

C Copyright 2005 Troyer Inc.

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REAR SUSPENSION 1.

Checking Rear for Straitness: A. This is something that should be done every week. If your rear is bent, it can make you chase a problem front to back and never find it.

B. The easiest way we have found to do this is to bolt a straight edge to the face of the drive flanges.

C. Then measure from side to side as you rotate the hub.

2.

Rear End Alignment: A. Blocks between rear and frame: LR 4 1/2” RR: 4” B. In a Troyer car, we put a hole in the roll cage to make this job easier for you. To properly square the rear end, you must remove the left rear cali per on all cars prior to 2001.

C. To square the rear end, you should have your ride heights set, and your radius rods and panhard rod in the location that you are going to run.

D. We measure from the front to the axle housing to the center of the 1/8” hole in the roll cage.

‘85-’00: 17½” ‘01-’03: 17 ½” left and 17 5/8” right E. Radius rod angles for 2001 3-link cars.

LR: 3o up RR: 5o up F. To locate the rear end from left to right, we measure from the center of the rear center section to the inside of the right side frame rail.

‘85-’00: 15” ‘01-’03: 13”

3.

Roll Steer: A. We do not recommend using roll steer on a flat or rough track.

B. Use roll steer to help the car through the corner or to help you get off the corner.

C. Move the right rear rod to the bottom hole of the rear end and the top hole on the left rear of the rear end to make the right rear wheel move back and the left rear move ahead when body roll occurs while cornering.

We will call this negative roll steer.

D. As body roll occurs, the right side of the chassis will lower which will level out the right rear radius rod. This in turn will move the right rear wheel

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Asphalt Modified Set-Up & Technical Guide

E.

F.

back which loosens the car.

Putting the left rear radius rod in the top hole on the rear end will allow the left rear wheel to come ahead as the car rolls into and through the corner. This is caused by the left rear radius rod going from a near level condition to a 10-15% angle. This also loosens the car.

A common practice to help a car that has an entry and apex push is to put the rods in these two positions and run a spring rod on the right rear radius rod which will let the right rear walk ahead under acceleration. To tighten the car back up while still letting the car roll into the corner and through the apex with the rear having “negative” roll steer, to help eliminate a push condition.

4.

Right Rear Radius Rod: A. A solid link will not allow the rear end to move front to back, except when body roll occurs.

B. A rubber bushing in front of the right rear radius rod will allow the right rear to move ahead approximately ¼” under acceleration. This will tighten up the car and let the right rear move back while braking for corner entry, which will loosen the car.

C. The spring rod is very popular in asphalt modifieds. Depending on the rate of the spring you use, the spring rod will allow the right rear to move from ¼” to 1 ¼”. This has the same effect as the rubber bushing, but on a larger scale.

5.

Tracking Right Side Wheels: A. Always run the same sized offset wheels on the right side.

B. The most common way to check this is to use a string.

C. We recommend measuring from the inside of the rear wheel to the out side of the chassis. Square the front tire to the chassis and measure from the inside of the front wheel to the outside of the chassis. The measure ment should be equal on 1997 and newer cars. There should be a 2” dif ference on ‘85-’96 cars.

6.

Wheel Offsets: LF: 15 X 6 RF: 15x5 LR: 15x5 RR: 15x5

Asphalt Modified Set-Up & Technical Guide

Lancaster Sportsman: LF: 13x4 RF: 13x3 LR: 13x3 RR: 13x3 C Copyright 2005 Troyer Inc.

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TIRES *NOTE: The information provided is not necessarily the opinion of the t ire manufacturers.

1.

Mounting New Tires: A. Inflate right side tires to 40 psi and immediately deflate to 15psi.

B. Inflate left side tires to 30 psi and immediately deflate to 10 psi.

C. Check your stagger at this time.

D. The stagger should be within ¼” of the desired amount. If it isn’t, try the same procedure with other tires until you get the correct stagger.

E. If you use a set that doesn’t size up well, you will have trouble maintaining you desired stagger.

F. For consistency on the race track, you should either use air or nitrogen all the time, not both.

2.

Scuffing New Tires: A. Bring the tires up to temperature slowly, making sure not to spin or slip the tires.

B. This is the time to get an accurate stagger check.

BRAKES 1.

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Breaking In Rotors and Pads * See enclosed Wilwood information on rotors and brake pads.

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Asphalt Modified Set-Up & Technical Guide

GENERAL INFORMATION 1 . Suggested Shocks. *NOTE: Call for specific applications.

Recommended base line setup...

Left Front Right Front Left Rear Right Rear

KONI 5325/2 5325/1 7325/2

Carrera 6255 6255 6176-5

AFCO TAF54-7 TAF54-6 TAR74-6

7325/0 6175 AC750 TAR75 * CALL FOR PENSKE SPECIFICATIONS.

2.

Suggested Springs.

A. Standard starting point: LF: 500 RF: 500 LR: 200 RR: 200

3.

Suggested Sway Bars.

A. B.

Pro AC557 AC556 AC74-6

Standard track: Fast, high bank:

Splined Bar 300 350

Bilstein 270-90 270-90

208-72 or 230-78 208-72

Fast, high banked track (Thompson): LF: 550 RF: 550 LR: 200 RR: 200

Howe Bar 1 1/8” 1 1/8”

4.

Suggested 4-Link Rod Measurements & Angles. o A. Left side top: 19 1/4” center to center/1.5 o B. Left side bottom: 20 1/2” center to center/1 o C. Right side top: 20 3/4” center to center/2.5 o D. Right side bottom: 22” center to center/2 E. Panhard bar height: 9” inside and 8 3/4” outside from ground to center *NOTE: Exact measurements may vary but index top of cage ahead 3/4” from level.

5.

Suggested Panhard Bar & Torque Arm Location.

A. Left side panhard bar. Inside: 9” (ground to center) Outside: 8 3/4” o B. Right side panhard bar. Middle hole rear 1 up to outside C. Use left side torque arm with right side panhard bar.

D. Use right side torque arm with left side panhard bar.

Asphalt Modified Set-Up & Technical Guide

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TROUBLE SHOOTING 1.

Corner Entry Push: A. Check stagger and increase if necessary.

B. Check tire temperatures and look at tires.

C. Check brake bias. Be sure not to have too much front brake.

D. Check shock travel.

E. Soften anti-roll bar.

F. Increase ackerman.

G. Soften right front spring or stiffen left front spring depending on shock travel and previous experience.

H. Even up rear spring rates if right rear is softer than left rear.

I. Put negative roll steer into rear.

J. Raise panhard rod.

K. Increase front percentage.

L. Put more rebound in left rear or right front shock.

2.

Corner Exit Push: A. Check stagger and increase.

B. Check tire temperatures and look at tires.

C. Check shock travel. If the right rear shows excessive travel, increase spring rate.

D. Decrease wedge.

E. Eliminate split in rear spring or stiffen left front spring.

F. Eliminate spring rod.

G. Raise panhard rod (normally, not above center).

H. Put negative roll steer into rear.

I. More rebound right front shock.

3.

Corner Entry Loose: A. Check stagger and decrease.

B. Check tire temperatures and look at tires.

C. Check brake bias (less rear).

D. Check shock travel. Look for excessive shock travel.

E. Increase wedge.

F. Stiffen right front spring or soften left front spring, depending on shock travel and prior experience.

G. Lower panhard rod.

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Asphalt Modified Set-Up & Technical Guide

4.

H. Make sure car does not have negative roll steer.

I. Put positive roll steer into rear.

J. Less rebound left rear shock.

Corner Exit Loose: A. Check Stagger and decrease.

B. Check tire temperatures and look at tires.

C. Check shock travel.

D. Increase wedge.

E. Stiffen left rear spring or soften right rear spring, depending on shock travel and prior experience.

F. Lower rear panhard rod.

G. Install spring rod.

H. Put positive roll steer into rear.

I. Increase rear percentage.

SWEET CAR LF Strut 23” 26 1/2” C to C RF Strut 21” 24 1/2” C to C

LF Lower A 15 3/4” C to C RF Lower A 16” C to C

LF Upper Mount in lower holes o to achieve 8 up hill to tire. .550 tapered spacer

RF Upper Mount in upper holes o to achieve 4 up hill to tire .550 tapered spacer plus approx. .250 more spacer

LF Lower & RF Lower Inner heim .625 spacer under heim & .375 on top.

Outer uniball .800 spacer between spindle & lower A .250 on top of spindle for bolt take-up.

LF lower angle 1.5o up hill to tire

Asphalt Modified Set-Up & Technical Guide

RF lower angle .5o up hill to tire Roll Center 2 1/4” up 4” left

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‘01-’03 PINTO FRONT END GEOMETRY & ANGLES Lower A-frame C to C: LF 12 5/8” RF 15” LF Strut 14” 18” C to C. RF Strut 15” 18 5/8” C to C Cut 1 1/4” off the LF inner tie rod.

Upper A-Frames: Lower holes on both sides.

Upper A-Frame Angles: LF 10o up to tire RF 7o up to tire Lower A-Frame Angles: LF .5o up to tire RF 1o up to tire Approximate spacing to achieve the above angles.

Lower A-Frames: LF 3/8” inner/.800 outer RF 3/8” inner/.800 outer Upper A-Frames: LF .925

RF .550

Roll Center: 2 3/4” above ground and 3” to left of center.

These measurements are based on 2” LF chassis height, 2 3/4” RF chassis height, 5” offset wheel on RF and 6” offset wheel on LF.

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Asphalt Modified Set-Up & Technical Guide

NOTES: _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________

Asphalt Modified Set-Up & Technical Guide

C Copyright 2005 Troyer Inc.

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Left Side

INITIAL SET-UP SHEET

Right Side

REAR STRUTS Upper Length (Center to Center) Lower Length (Center to Center) Upper Angle Lower Angle Torque Arm Lower A-Frame Measurement (Center to Center) Strut (Center to Center) Inner Pivot (Ground to Center) Uniball (Ground to Center) A-Frame Angle (+angle = higher at tire) Upper A-Frames Length (Center to Center) Inner Pivot @ Front (Ground to Center) Inner Pivot @ Rear (Ground to Center) Uniball (Ground to Center) Upper A-Frame Angle (+angle = higher at tire) Tie Rods Length (Center to Center) Steering Arm Length (Center to Center) Angle (+angle = higher at tire) Thickness of shims at spindle Panhard Bar Length (Center to Center) Left Side Location Right Side Location Angle (+angle = higher on right) 14

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Asphalt Modified Set-Up & Technical Guide

TRACK: HEAT START: FIN: TIME TRIALS FAST TIME:

DATE: CONSI START: YOUR TIME:

CASTOR

CAMBER:

DRIVER: FIN: FEATURE START: FIN: FEATURE TIMES BEGINNING: END: STAGGER:

FRAME HT FRAME HT LF WHEEL RF WHEEL BUMP STEER PSI. COLD: HOT: PSI. COLD: HOT: BUMP STEER: TIRE SIZE TIRE SIZE REB: RF SHOCK COMP: REB: LF SHOCK COMP: LF SPRING RF SPRING WHEEL WEIGHT WHEEL WEIGHT (PIVOT) FRAME HT FRAME HT (PIVOT) LS PANHARD BAR LR WHEEL RR WHEEL RS PANHARD BAR PSI. COLD: HOT: PSI. COLD: HOT: (GROUND) (GROUND) TIRE SIZE TIRE SIZE LR UPPER ROD ANGLE LR SHOCK COMP: REB: RR SHOCK COMP: REB: RR UPPER ROD ANGLE LR LOWER ROD ANGLE LR SPRING RR SPRING RR LOWER ROD ANGLE WHEEL WEIGHT WHEEL WEIGHT REAR REAR END END REAR % GEAR LEFT SIDE% REAR STAGGER DIAGONAL% FUEL LEVEL COMMENTS: ___________________________________________________________________ ________________________________________________________________________________________________________ ________________________________________________________________________________________________________ CASTOR

CAMBER:

STAGGER:

FRAME HT FRAME HT LF WHEEL RF WHEEL BUMP STEER PSI. COLD: HOT: PSI. COLD: HOT: BUMP STEER: TIRE SIZE TIRE SIZE REB: RF SHOCK COMP: REB: LF SHOCK COMP: LF SPRING RF SPRING WHEEL WEIGHT WHEEL WEIGHT (PIVOT) FRAME HT FRAME HT (PIVOT) LS PANHARD BAR LR WHEEL RR WHEEL RS PANHARD BAR PSI. COLD: HOT: PSI. COLD: HOT: (GROUND) (GROUND) TIRE SIZE TIRE SIZE LR UPPER ROD ANGLE LR SHOCK COMP: REB: RR SHOCK COMP: REB: RR UPPER ROD ANGLE LR LOWER ROD ANGLE LR SPRING RR SPRING RR LOWER ROD ANGLE WHEEL WEIGHT WHEEL WEIGHT REAR REAR END END REAR % GEAR LEFT SIDE% REAR STAGGER DIAGONAL% FUEL LEVEL SUGGESTIONS: ________________________________________________________________ ________________________________________________________________________________________________________ ________________________________________________________________________________________________________ ________________________________________________________________________________________________________ Asphalt Modified Set-Up & Technical Guide

C Copyright 2005 Troyer Inc.

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