having cooling issues at full boost on the track

I'm having cooling issues on the road course when racing on hot days.

The car runs 190-195 all the time around town and on the highway. Never has cooling issues. However on the track where I'm at full throttle most of the time it tends to run as high as 245. At full throttle I'm getting about 14lbs of boost. this weekend I could get about 4 laps (8 miles) with the temps around 200, then it would start climbing. Of course as the temps go up - the power goes down. The outside temp was about 95F.

I've done all the normal stuff for cooling. Griffin alum Radiator(400Hp version), 180 tstat, reprog fans to come on earlier with eectuner, 800CFM fan on IC.

Because I'm running at 4500-5500rpm much of the time I tried using underdrive pulleys to slow the waterpump down thinking that it would give the system more time to disipate the heat via the radiator. Bad idea Makes it worse.


Any ideas how to improve the cooling in this situation?

cooling issue

I might go ahead and have the cooling system sniffed for combustion gasses, thinking a head gasket may be seeping under load (14 lbs. boost). If this is the case, your cooling system is definately going to run at those hi temps.
JMHO...
Bill

Good idea. I thought about the heads gaskets because I was losing some water from the cooling system (ie. I had to add water between runs with no apparent leaks), but wasn't sure how to test. Can any shop do the sniff? What type of equipment do you need to do that?

I'm probably going to go ahead and pull the motor here soon to do a freshen up on the bottom end and open the heads up a bit. It's due, 136k on the clock with all original internals. This was the last event until next spring. I would like to have it ready then so we can run the full season in the NASA Time Trials next year.

Agreed, do the headgaskets now before engine damage results. One WOT session with traces of water in the oil will destroy the crank.

Mansier Motorsports is running their SC in NASA American Iron class and report that with a large griffen radiator (and underdrives) and no fan at all temperatures do not exceed 180 on the track (of course it's only in the 80's here in Ohio. ). I would be pretty certain you have headgasket issues. Most likely very slight but nonetheless...

no water in the oil. Yet I've now got 6 months before the next event(season). Guess what I'm doing over christmas

BTW, it's not done this on any of the prior events, so the HG is the most likely cause