Track Day 04 - Takeaways & C5 Corvette Square Setup W/ Federal 595RS-RR tires at the track!
After a brief hiatus from my previous track day, I was able to get the Corvette out with the square tires and wheels for a track day at Streets of Willow Springs. I again got out with Tracked LLC for an excellent track day. Just like last time, attendance was notably down due to very high forecasted temperatures of exceeding 100 degrees. The temperatures infact peaked at 115 degrees, taking a good chunk of the attendees off of the track as well. In the end we were able to get 30 minutes sessions and then just open sessions until the end of the day. This was a refreshing change from my laguna Seca day where I had to wait an hour and 40 minutes between sessions!
While my previous track day was 106 degrees out and I was able to push 282 degree oil temperatures, at this track day where it was 113 out the highest oil temperature I saw was 264 degrees. I attribute this drop in oil temperature to a significant difference in the two tracks. Buttonwillow I was often wide open throttle at high RPM's for significant portions of the track. At Willow Springs there were so many more turns that I was often using maintenance throttle to keep my weight transfer correct for handling, and thus not spinning high RPM for prolonged periods of time.
One interesting improvement over my first track day here was that I was not experiencing brake fade issues. Having gone with stainless lines, Motul RBF 600 brake fluid, and venting the wheel well up through the hood louvers all seems to have alleviated much of my braking concerns.
The Square setup with the Federal 595RS-RR tires definitely provided an interesting result throughout the track day. I went into this expecting a substantial improvement in grip and handling both from the wider front tires (275 up from 245) and the jump to a "grippier" 200 treadwire tire. This did not wind up the case.
At first, I felt I had less grip than I did with the Falken 510s and I could get the car to slide pretty easy. That said, the slides with the 595RS-RR's were very very predictable and controllable, that much more so than the Falken 510s. I no longer was able to oversteer, and found slides to be either balanced 4 wheel pushes, or oversteer. It was all quite controllable.
Throughout the day though I became more accustomed to the tires, and I can say that I believe the tires did infact yield an improvement, I just believe the improvement is quickly lost to the very soft suspension my Corvette has. With the softest spring rates of any C5 Corvette (me being base vs the Z51 or Z06 springs) and the 23 year old very soft shocks and undeniably aenemic sway bars, I had a lot of body roll while cornering and pitch when braking. These issues are also quite apparent in the cornering pictures I got from the track day.
The new goal before tmy next track day is to upgrade the suspension. Sway bars and coilovers should do the trick to help make the Corvette handle that much better on the track. I've heard it'll create a less than pleasant driving experience on the street, but this car is quickly becoming more and more track day oriented.
Video from the track day: