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Suspension Setup

 
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dale



Joined: 22 Aug 1999
Posts: 3085
Location: Seattle, WA USA

PostPosted: Wed Jan 05, 2005 10:16 am    Post subject: Suspension Setup Reply with quote

Some advice on suspension setup from fellow local racer, Greg.

Suspension Setup

1. Research

a. Find out what your car should be set up like by asking other racers with similar cars and checking race alignment shops for recorded data.

b. Research the tracks that you plan to drive.

c. Determine the cost of the suspension mods and trim to fit your budget by prioritizing these mods based on bang for the $
2. Sourcing

a. Shop around and weigh vendor benefits and performance.

b. Purchase parts in time to get them installed before big race.

3. Measure gains

a. Make one mod at a time and drive that set up a few times to determine the benefit from your $$

b. Keep a driver log recording your tires, track conditions, driver ability, lap times

Shocks

Shocks may be the most important modification you can make. If the wheels stay in contact with the track you can drive the car deeper, faster, and still be in control. Shocks keep the wheels from bouncing and allow the wheels to return to the track after a big bump. Shocks are quick transition dampers.

Sway bars

Sway bars – or anti sway bars if you prefer – help keep the car flatter in turns. A flatter car has more equal traction on all tires.

Springs

Springs allow bumps to be absorbed, determine the ride height, the ultimate sway, roll, for and aft pitch for a given g force. Spring height if adjustable helps corner balance the car so all tires share traction the best.

Race setup –

Shock selection – shocks must match spring rates and track conditions. A damping analysis can be run if you have all the critical car data. If you don’t have the data go with proven combinations from people who understand race cars.

Corner balancing –

Setup scales on flat ground

Warm up scales – keep temperature constant if possible

Inflate tires to same pressure – higher than normal –say 45 lbs

Measure weights with driver in the car with normal fuel load

Add ballast if necessary to get to required race weight

Adjust spring perches to get desired corner weights

Keep ride height legal[Pro3 5"]

Opposite corners should sum to the same weight

Fore and Aft weight should be as close as possible

Caster Camber –
Adjust per your research

Drive the car with a one size fits all setup until you have the driver skills to know the difference

Adjust the caster camber per the track driven and weather conditions when you learn what works. Practice new set ups on test and tune days or on practice session, but not for the race.
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