I posted this under a thread titled "Atco Track Rental - Update". I think this title will get more attention for the question regarding heatsoak.

Just got back from Atco. Had a fun morning with the Vette gang. We knew it was going to be too hot to get great times, but we made the best of it. Saw some awesome 9 and 10 second vettes.

My quickest pass of the day was my first - 12.161 @ 117.08 mph, 1.911 60' time. It was already 75 degrees on my vehicle display for that run (at about 10:25 a.m.) I hot-lapped it and immediately made another run. I ran a 12.184 @ 116.16 mph with a better 60' time of 1.893. I was surprised that the drop-off wasn't much greater.

Made a bunch of passes as the temperature rose. FYI - if you launch in second gear, you'll run a 12.8 @ 115.

I was having progressively more wheelspin off the line as the fuel level went down, and my 60 foot times were creeping up to 2.132 as the ESP interceded more than usual. After a 12.474, I put ten bucks worth of fuel in it and made my last run - a 12.167 @ 117.36 with the vehicle display showing 84 degrees and a 60' time of 1.930.

I am pleased with how the car did, but confused. How did I manage such high MPH on such a hot day? On much cooler days, I've gone through the traps slower. Also, with my relatively consistent back-to-back runs, are we making heat-soak a bigger issue than it really ought to be?

 

Thanks for the post Enzom.

Quick question....I am all set to hit the track this weekend.

Any tips on when to launch.....you trying to punch it/release brake as last yellow is coming off.....any tips you could share.

Thanks for any info.

 

I don't think anything I do is going to help you with all the horses under your hood.

I assume you are running street rubber other than the stock Contis. I would roll into the gas at the last yellow. For sake of completeness, here's what I do, in more "baby detail" than you probably need. But I figure somebody else might need a primer on it:


Suspension set to comfort. Rear tires at 22 psi. Some people like to inflate the fronts to 40 plus. I don't bother with that. I actually experimented today with starting my runs with the front of the car elevated via the button near the suspension settings and lowering the car after the first hundred or so feet. Not sure it did anything.


ESP Off, foot on the brake. Bring the revs up and spin your tires for a second or two. This is mostly just to clean the surface of the tires and get rid of any water you may have run over. People have mixed views on this, but heating street tires is of limited value. ET Streets and Drag Radials are a whole different animal.

Turn the ESP back ON. Slowly approach the tree. Make sure you are "in the groove". If your car is centered, you will be fine.

When you trip the first row of staging lights, stop. Creep slowly until the second set of staging lights barely trips. For those not familiar with the terminology, this is called "shallow staging". Your e.t's are generally quicker with shallow staging, but your reaction times worse. Because e.t.'s are what matters 99% of the time, shallow staging is better.

When both staging lights are lit (two rows of double yellow lights), I press harder on the brakes and give it just a bit of gas. Just enough to feel the car start to load up, but not so much as to require you to press the brake even harder. On the last yellow light, I let off of the brake and roll into the gas.

IF I WERE DRIVING YOUR CAR, I would not load up on the brakes at the start. I think you'll break traction. I'd experiment with just rolling into the throttle. Not launching aggressively enough will do far less harm to your run than giving it too much gas and breaking traction. E.T.'s are made in the first 60 feet. Especially with our cars.

GOOD LUCK!!!!!!! Please let us know how you do.

 

Enzom,
I ran the exact same time two years ago when it was stock to the hundredth.
You will not have as big a problem with heat soak as some modified cars because you did not up your boast pressure. When you change the pulley and lean the fuel mixture with the ECU upgrade, heat becomes a real problem.