Embed Size (px)
Citation preview
www.DavidMurrayRacing.com
2
2011
DM
R M
odifi
ed S
etup
Gui
deMaintaining Your
Preparing your race car during the week is just as important as what goes on at the track during a normal night of racing. Failure to properly maintain your chassis or engine will not only cost your team valuable finishes, but increase the operating cost for your racing program.
Maintenance Tips•Schedule early in the week •Assign specific duties with a checklist•Make it a priority and take it serious•Develop a routine and stick to it
Chassis Maintenance
• Washing Your Car It is impossible to properly maintain a car that has not been cleaned. Bends, cracks, or failing parts can be overshadowed by dirt or mud on the frame or suspension components.
• Front Suspension Components Upper control arms, ball joints, tie rods and heims, center links and drag links should all be inspected. This includes tightening all nuts, bolts, and jam nuts. Examine suspension pieces closely for damage and to make sure they move freely. When tightening your caliper bolts, take a close look at your front hubs, rotors, and wheel studs for any signs of wear, cracks, or loose conditions.
• Rear Suspension Components Begin on one side of the rearend and work your way to the other. When tightening your caliper bolts, take a close look at your rear hubs, rotors, and wheel studs for any signs of wear, cracks, or loose conditions. Axle splines and drive flanges should be cleaned and greased on a regular basis. Two link brackets or birdcages need to be cleaned, inspected closely and lubricated as needed to ensure components are working properly. Inspect panhard bar and pinion mount for tightness and signs of wear.
• Body Panels and Braces Repair body pieces or panels as needed. Look for sharp edges or broken braces that could cause tire rub or injure a crew member while working on the car. Take pride in the appearance of your car to promote current sponsors and possibly attract new ones!
TECH NOTES:
www.DavidMurrayRacing.com 3
2011 DMR M
odified Setup Guide
• Check clutch fluid _____
• Check brake fluid _____
• Check brake pad wear _____
• Check caliper bolts _____
• Check transmission fluid _____
• Check rear end fluid _____
• Check hubs & rotors _____
• Check wheel bearings _____
• Check front suspension _____
• Check rear suspension & _____ lube heims
• Check drive shaft & grease _____
• Check & lube birdcages _____
• Check shocks _____
• Check & pre-load pull bar _____
• Tighten nuts & bolts _____
• Grease heims & ball joints _____
• Set caster & camber _____
• Check & set toe _____
• Check drive flanges & hubs _____
• Check safety equipment _____
• Scale race car _____
• Check water level _____
• Check / change engine oil _____
• Check power steering fluid _____
Weekly Maintenance Agenda
• Change / inspect oil filter _____
• Clean air filter & breathers _____
• Clean & inspect fuel filter _____
• Check fuel pressure _____
• Charge battery _____
• Set valves and check timing _____
• Check & lubricate _____ carburetor linkages
• Check belts & hoses _____
• Check electrical wires _____
• Check plug & coil wires _____
• Check header bolts _____
• Check mid-plate & _____ engine mounts
• Make sure distributor nut _____ is tight
• Check headers _____
Race Car Checklist
Date:______________ Gear:______________Track:_____________________
Trailer Checklist• Race suit / helmet / tear offs _____
• Tools / jack / pit equipment _____
• Fuel for race car / generator _____
• Replenish parts list _____
• Tires / wheels prepped _____
• Batteries charged (impact / winch) _____
• Cooler / refreshments _____
• Trailer tires (air pressure / torque) _____
4
2011
DM
R M
odifi
ed S
etup
Gui
de
Modified Scaling ProcessPreparing your race car is the foundation for a successful night or season. This is a tedious process that requires a basic routine with guidelines, and your dedication. The bottom line when it comes to setting up your race car; YOU GET OUT OF IT WHAT YOU PUT INTO IT!
Engine Setback• Measured from the front of the motor plate to
the face of the rear end housing.• Example: 70 1/2” to the face of the
housing tube = 72” to the center of the axle tube.
Remove Right Rear Axle• Sliding the axle out of the housing decreases binding due to ratcheting of axles.• Gives a more accurate reading on rear bite during scaling process.
Set Tire Pressure and Stagger
Left Front Right Front11 psi 15 psi
Front Stagger3/4"
Rear Stagger11/4" - 11/2”
Left Rear Right Rear10 psi 13 psi
Measuring Your Race Car• All measurements and angles are to be completed with the car sitting at the proper ride heights.• All “points of reference” need to be in good condition in order to get accurate measurements on a consistent basis.• Using index plates or other set up tools ensure accuracy.
Note: The measurement is taken on the front side of the mid plate
TECH NOTES:
www.DavidMurrayRacing.com 5
2011 DMR M
odified Setup Guide
Check Fuel Level• Scale with race car full of fuel.
Fill All Fluids• This includes water level, oil, rear end grease, transmission fluid, and brake fluid.
Measuring and Setting Frame Heights• Setting your frame heights correclty, and maintaining them through the setup process, is crictical to the
accuracy of front and rear roll centers.• As you adjust your car during the scaling process you must verify your frame heights
are set to the correct measurement.• One note: the left rear must be at least 6” with the driver in the car.
Modified Frame HeightsLeft Front Right Front
9 5/8” 9 7/8”
Left Rear Right Rear6 1/2” 6 1/2”
TECH TIP:Front ride heights are measured thru the outer most factory body hole, from the ground to the top edge of the frame hole.
Rear ride heights are measured directly below the rear four bar mounts to the ground.
Bottom of rear end housing tube to top of underslung bar on right rear is 21/2” to 25/8” with race car full of fuel.
Add Ballast Needed To Make Weight• It’s a good idea to start with your lead in the same location for the scaling process.• Check your notes from the previous night of racing to see if any weight was moved, taken off, or added to
your race car.
TECH NOTES:
6
2011
DM
R M
odifi
ed S
etup
Gui
de
Squaring Your Rear End• Accurately positioning your rear end in the car is critical to your overall handling.• If your rear end is not properly located, recommended adjustments will not provide desired results.• Properly locating your rear end consists setting your panhard bar, measuring the rear end left to right, and establishing proper four-bar lengths.• All of this must be done without changing the engine set back measurement.
Panhard Bar Set UpPanhard Bar Length
19"
Note: Panhard Bar should be mounted at the center line of the pinion.
Measured center of heim to center of heim.
Note: Start with panhard slide clamp 5” up from top of underslung. Measure from bottom of panhard bar bracket.
Upper Left Bar4th Hole
Upper Right Bar5th Hole
Lower Right Bar3rd Hole
Lower Left Bar4th Hole
Setting Your Four-Bar Angles• Hole location is counted from the bottom.• Bar position is designed for a starting point at the beginning of the night.
Note: If you run a brake floater the bar can be mounted on the outside of the four-bar bracket
TECH NOTES:
TECH NOTES:
www.DavidMurrayRacing.com 7
2011 DMR M
odified Setup Guide
Left Side Measurement91/4”
Measure from the outer edge of the left rer underslung to inside of rotor.
To double check, run a string along the left front and left rear tire, making sure they are in line with one another.
Frame Rail
Locating Your Rear End
Pinion Angle8° to 9°
Set Pinion Angle• Setting pinion angle is the last thing you do after scaling the car, with car at ride heights.• Before you set your pinion angle, check your torque link to make sure pre-load settings have not changed.• To get the most accurate reading, place a degree finder flush on the pinion mount.• After you set the pinion angle, double check the pre-load on your torque link.
Left Upper Trailing Arm17”
Left Lower Trailing Arm15”
Right Upper Trailing Arm17”
Right Lower Trailing Arm15”
To ensure your rear end is in the car square, four-bar lengths need to be measured accurately. Four-Bar Lengths
TECH NOTES:
TECH NOTES:
TECH NOTES:
8
2011
DM
R M
odifi
ed S
etup
Gui
de
Indexing Bird Cage0°
Zero Index Birdcages• This needs to be done while the car is sitting at correct ride heights.• The left birdcage needs to be indexed with the top four bar in the middle hole of the bird cage.• Bird cages need to be set at zero degrees. This can be measured at the top of the bird cage
(if surface is flat) or at the bottom along the shock mounts.• Any changes made to adjust the bird cages must offset each other. For example, if you shorten the top bar
one turn, you must lengthen the bottom bar one turn. This will ensure that the position of your rear end does not change.
• Indexing of the bird cage will change ride heights and rear bite.
TECH NOTES:
Setting Your Front End• Set your caster, camber, and toe in that order.• Double check your gauge to verify proper way to set caster.
Left Front Caster+2.5° to +3.5°
Left Front Camber+2.5°
Right Front Caster+5° to +6°
Right Front Camber-3°
Caster
Camber
Toe-Out1/8"
Toe
Set Car On The Scales• Make sure your scale pads are level and zero them out before rolling car onto scales.• To improve consistency, it’s a good idea to scale your car in the same location if possible.
www.DavidMurrayRacing.com 9
2011 DMR M
odified Setup Guide
Left Side %52.3%
Cross %49.5%
Bite or Wedge40 to 60 lbs
Rear %58.5%
Modified Scale Summary
Scaling Quick Reference Guide
1. Measure Engine Setback2. Remove Right Rear Axle3. Set Tire Pressure / Stagger4. Check Fuel Level5. Fill All Fluids6. Add Ballast As Needed7. Measure And Set Frame Heights
8. Set Four Bar Angles9. Square Rear End10. Set Pinion Angle11. Zero Index Birdcages12. Set Front End13. Double Check Frame Heights14. Set Car On Scales
Left Front Right Front10 psi 15 psi
Front Stagger3/4” to 1"
Rear Stagger1” to 2"
Left Rear Right Rear10 psi 14 psi
Upper Left Bar4th Hole
Upper Right Bar5th Hole
Lower Right Bar3rd Hole
Lower Left Bar4th Hole
Modified Frame Heights
Front Suspension Setup
Tire Setup - 2" offset wheels on all four corners
Recommended Base Line Setup
Four-Bar Setup
Left Front Right Front9 5/8” 9 7/8”
Left Rear Right Rear6 1/2” 6 1/2”
Left Front Caster+3.5°
Left Front Camber+2.5°
Right Front Caster+5°
Right Front Camber-3°
Toe-Out1/8"
Note: ballast is only added to make weight, not for traction purposes.
Note: It is crucial that you check ride heights after making adjustments.
Note: based on a 200 lb driver - scaled without driver in the car.
Heavy Track18 1/2”
Dry Slick Track18 7/8”
Left Rear Chain Drop
Note: Left rear chain drop is measured from bottom of the top frame rail to top of rear end housing tube. 5 1/2” maximum drop at the tire.
10
2011
DM
R M
odifi
ed S
etup
Gui
de
Modified Shock & Spring Technology
Left Front600 lb
Right Front650 lb
Left Rear200 lb x 16"
Right Rear175 lb x 13"
Spring Recommendations
Heavy Track Shock Setup
Slick Track Shock Setup
Rough Track Shock Setup
Left Front40 Comp: 40 Reb
Left Front30 Comp: 30 Reb
Left Front40 Comp: 40 Reb
Right Front50 Comp: 30 Reb
Right Front70 Comp: 30 Reb
Right Front40 Comp: 40 Reb
Right Rear30 Comp: 30 Reb
Right Rear30 Comp: 30 Reb
Right Rear40 Comp: 40 Reb
Left Rear30 Comp: 50 Reb
Left Rear20 Comp: 60 Reb
Left Rear20 Comp: 60 Reb
TECH NOTES:
TECH NOTES:
TECH TIP:Keep in mind that manufacturers have different ways of reading shocks. When choosing a brand, make sure you know the difference in 7" and 9" part numbers. Also, companies such as AFCO read compression first, rebound second, while others, such as BSB and Bilstein, read rebound first, compression second.
Note: If driver weighs more than 210 pounds you need to run a 250 pound spring in the left rear.
Note: The following shock setup information is based on BSB part numbers.
www.DavidMurrayRacing.com 11
2011 DMR M
odified Setup Guide
Torque Link Settings• Use 1200 lb torque link spring.• Mounts in the top hole of the frame (drive shaft hoop).• Mounts in the front, middle hole of the “Bat Wing” mount on top of rear end.• Use 1/4” pre-load on spring. Using red biscuit you want 1/8” pre-load.• Pinion angle on rear end set at 8° to 9°.• BSB 7650 pull bar with red & blue biscuits with 1/8” pre-load.• Adjust brake biscuit nut all the way.• Pull bar length (new style) = 32 1/2”
TECH NOTES:
12
2011
DM
R M
odifi
ed S
etup
Gui
de
Championship Tuning Guide
