We're running the June Jam at Lowe's Motor Speedway, and we didn't get much track time on today due to overheating issues. The water temp got to 235 and the oil saw about 225. It ran hot when I kept my foot in it at high speeds.

I'm looking for anything I can do to cool it down enough to complete the race tomorrow.

Setup:
81 JY motor - 1st time it's run in the car
81-83 oil cooler setup - blocked bypass
stock 81-83 radiator - gutted T-stat and blocked bypass
RB small crank pulley, all other pulleys stock
no fan or shroud, under tray is in place


Things I'm thinking to try:
rejet carb - slightly bigger secondaries
change timing - currently running about 12 leading advance.

I can't get a different radiator or different pulleys in time. I'm already running water wetter. Any other ideas on how to cool this down enough to finish a 30 minute sprint?

Thanks,
Neil

 

Hmm... 235 is HOT for water wetter + gutted thermostat. To get the best effect, run just water and water wetter with no antifreeze(you're probably already doing that though) Maybe your coolant o-rings are leaking? It seriously sounds like combustion heat is getting to it. Check for air bubbles in the radiator when it's idling. I live in NC too, about an hour from charlotte in the piedmont. If you need anything, I can try to help ya.

 

Thanks for the reply.

I don't think the Orings have failed. Our first engine went that way, and we had very hard starting and coolant pushed out into the overflow tank when that was the problem.

For Sunday, we wound up changing the carb to one with different jets, and we got a break as the temp was only about 80 deg. The car made it through the sprint with temps just under 230. I think the radiator isn't flowing well enough. I don't think the carb made any real difference.

Just a dumb question - would you expect to get a one for one drop in coolant temp to ambient? Ex. if it runs 235 at 90 deg ambient, would you expect 225 at 80 deg ambient? I would not think it's that simple, but I don't know for sure.

 

my n/a fc had serious overheating issues as well. i got rid of the thermostat and had an undertray in place which helped a lot. however it still overheated after about 8 laps or so. anyways, i added a huge (16" x 22") electric fan with shroud from an old ford topaz and this seems to have fixed the problem. i just wired it up to the battery with a on/off switch and turn it on after 2 laps. it works great cuz it help a bunch to cool the car at lower speeds, like through sharp corners and such. so give it a try and see if it helps, i picked up my fan at a junkyard for 40bucks canadian. good luck