TEIN Engineer, R. Takizawa and I went to ButtonWillow raceway last Thursday, March 18th to test with the Evasive Motorsports CT9A. The EVO 9 will be running in this weekend’s Redline Time Attack at Buttonwillow Raceway in Buttonwillow, CA. Normally the Evasive EVO runs in the Limited or Modified class which is on R-Compound tires but for this event they will enter the Super-Modified Class wearing Yokohama slicks.
Mike of Evasive told us of his plans a few months ago so we revalved the dampers and suggested stiffer spring rates to match the grip of the slicks. Without having data on the tires our suggested spring rates and new valving were all calculated guesses. The actual track testing and driver feedback would let us know if the suspension needed minor or major adjustments (minor = damping force adjustments, major = revalving).
Pictured – Mike getting ready to go out for session 1.
In the first lap of the first session we witnessed Mike start a 25MPH parade lap and immediately knew something was wrong after the first few corners. Mike was getting a bad vibration over 25MPH on acceleration.
His support team comprised of Kel, Brad and Hugh quickly went to work to diagnose and fix the problem. The culprit was worn axle tripod housings. Without having spares axles the crew went to work on a fix and the car was vibration free a couple hours later. R. Takizawa did a quick alignment adjustment and the car was back on track.
Pictured – R. Takizawa adjusting front toe while Brad and Kel take a much needed break after a scramble to get rid of the vibration.
After Mike got a feel for the car and a few semi-open laps we were able to gather some suspension feedback. At first there was slight understeer at corner exit so a front damping force adjustment was made. The change worked a little too well and resulted in a slight oversteer. So TEIN Engineer R. Takizawa made another slight change in damping force. Overall the stiffer spring rates, damper revalving and small adjustments resulted in a car that was predictable and easy to control. More suspension tuning is definitely needed but at this point the car is ready to compete for the first time in the 2010 season. During the next testing phase we may try stiffer sway bar or slightly stiffer springs, alignment changes, and of course more damping force adjustments.
Pictured – In the hot pits. Mike driving, R. Takizawa making damping force changes, Brad checking tire pressures, Kel taking tire temps. and Hugh recording data.
A look at the Voltex front aero which keeps this EVO planted.
We wish Evasive Motorsports the best of luck at the Redline Time Attack.