This was the event where we learned that we needed to get a set of race tires if we wanted to be competitive in Time Trial clubs like COMSCC. It was the first time we had run our Cobra against experienced racers in the dry. To put it bluntly, we got creamed.
This Time Trial was on October 14 and 15, and this time used the South Oval configuration, which we both found a bit more intimidating than the South Chicane.
Nate had bought an excellent Chevy van and nice new trailer. The van has plenty of room for tools and equipment and even a special reclining passenger seat for resting between sessions and on the road. What luxury!
Best of all, we no longer have to look forward to driving the topless, leaky Cobra for hours through bad weather getting to and from the track.
Of course, this meant that the weather this weekend was clear and gorgeous. At least now we could concentrate on getting the most out of the car.
Unfortunately, we discovered that the most we could get out of the car was the slowest and second slowest times in Street Prepared A. The car was running well, and we were both more comfortable with it than before, but the best either of us could do was my 1:22.9 in practice. The other SPA cars were doing between 1:11.7 (Leos Kubec in a monstrous Porsche) and 1:21.
We spent some time walking around the paddock, looking at other cars and talking with their drivers. We learned that we were the only team running regular street tires. Everyone else in the club had a set of DOT-legal race tires, mostly either Hoosier, which were nearly slicks and very soft, or Kumhos, which had a bit more tread but were equally soft.
These race tires are technically "street tires", with barely enough tread to qualify at the DOT as legal for the street, but with compounds so soft that they have a wear rating of about 30, vs 180 for our street Yokohamas and over 300 for most street tires.
We learned that the Hoosiers are perhaps a second quicker than the Kumhos at first, but the Kumhos are more consistent, delivering the same grip and lap times throughout their life, while the Hoosiers tend to go off after two or three weekends.
We also learned that race tires are good for anywhere from three to five seconds at Loudon. Four seconds would have put us into the middle of the class and made us the fastest Cobra.
After some discussion, and pondering the lap times, we concluded that, if we were going to continue doing these time trials, we needed to get another set of wheels and a set of race tires.
We also looked at seats while we were walking around. We both found that the stock FFR seats, which are replicas of the original Cobra seats, just didn't give enough lateral support under racing conditions. Even the street tires generate so much grip that we found ourselves clenching the wheel and pushing hard against the dead pedal just to stay in place. This not only consumes energy but makes it tougher to be precise and smooth, both of which are very important for fast lap times.
After looking at the type of seats everyone else was using, we decided to get a real racing-type seat as well.
Also we found that although the brake changes we'd made after the NERC event worked fairly well in the dry, the pedal still went down somewhat through the course of the weekend. We decided to look for ways to improve them some more. The event's chief instructor stressed the importance of using harder brake pads than are typically used for the street, and also of using braided stainless brake lines. We decided to do both.
Aside from getting trounced, we had a couple other embarrassments this weekend. We had a rather spectacular trailer mishap, but fortunately no one was hurt and the Cobra was only hurt cosmetically. Also the hood flew off the Cobra on the main straight, soaring way up in the air. Again fortunately no one was hurt and the hood was only dinged and still usable.
Some good things happened, though. I had some great dices during practice with Peter Fontana and his wonderful Mustang, and Nate and I both enjoyed getting to know the track and the car better in the dry.
We also collected some excellent data with our new G-cube, and after some struggles with the road course extensions in the beta GEEZ software I was able to generate some very useful plots of our best laps. The difference in styles between Nate and I was quite obvious and will hopefully help both of us to find some more time.
By the end of the weekend, we both got signed off for our COMSCC licenses, which is a relief because now we can run the time trial days even if we don't get into COMSCC's often over-subscribed practice days.