I had the same problem, we used a snap on coolant purge tool and problem was solved. All other tests we done and we cool, ie leak down etc. It could be a very small hole in the coolant line somewhere that lets air in. Don't worry to much.

 

Bad news here too....

I was driving to dinner the other night and I look at my temp gauge and the temps are abnormally high. So, I shut the car off, pull off the road, and lo and behold, the overflow tank is nearly filled.

Here are some facts:
1) There was no oil in the coolant.
2) There is no coolant leaking from the car.
3) I don't drive my car that hard, and I hardly ever use my 8.8lbs map, so it's 95% of the time on the wastegate pressure.
4) I drove the car from Orlando all the way back to school without so much as a hitch. Then as I'm going to dinner one night, the car just randomly overheats.
5) I don't have a built motor, so it's never been taken apart.

I'm going to be pissed if I'm lifting my heads because I don't even drive my car that hard, or that often. And I really don't want to build my motor just to have this happen again later on down the road.

I talked to some very knowledgeable people on the forum recently, and their consensus was that for a built motor car, 550whp was the limit to avoid headlift. I'm already out about 15K for my little setup as it is, and to spend another 10K (bringing the grand total to 25K for engine mods alone) seems crazy for only 550whp.

I wonder sometimes if the Z was just not meant to be boosted, but at the same time I love my car and wouldn't trade it for the world.

 

I would be willing to bet large sums of money that yours is coolant related. I don't know where the back coolant pipe attaches to the engine, but that is where my failure was at.

Didn't Sharif put yours together? If so, he will take very good care of you.

 

Glad it was nothing major and was a easy fix.

 

LOL-arent very knowledgable when my car made 490whp and lifted heads in less than 10,000 miles. HL can happen at most any power level, its all in the tune, cooling system, driving habits, etc. Too many variables to things fail at XXX whp.

Buy a spill funnell and see if you can purge air out of the system. That is your next step.

 

Is there a DIY for a coolant purge around here?

 

Very true. Excellent shop to do business with and thats why they stay so damn busy.

 

I know Sharif has my back. But this is an issue that I have to resolve myself as he is some distance away from me.

 

Ok, another question; should my fans be turning on at a certain temperature threshold?

 

James, i had a similiar issue a good while back. Temp gauge went crazy so i pulled over and eventually found the source. Turns out, my rad cap was loose and coolant was spewing everywhere. Now i know that you said you were NOT leaking coolant so I doubt its the same issue, but i just figured I'd throw that out there because it was an easy fix and no harm was done. GL with everything.

 

That's right, I forget that you are NC right?

It will all work out

 

Close. I'm in SC (Clemson). I know it will all work out but its still a pain in the ***. Thanks for the kind words though .

 

james do you have an aftermarket or stock radiator? I know we have the same setup basicly as far as mods go. i switched to Evans NPG a few months ago when i had the Samco hoses installed just for safety sake. I have a koyo radiator also though. Never experienced any overheating yet. Hope you can get it resolved easily.

 

Thanks mang. I considered that too. I have the Nismo radiator cap and its on there nice and snug.

 

I have stock everything. No hoses and no radiator.

 

since the incident have you tried driving the car to see if it repeated itself?

 

I started her up momentarily today. The car started getting hot again, but no coolant was in the overflow tank. My fans weren't coming on either.

 

When heat is on full hot and you blast it, is the air cool?

If so you have air in the system. Many posts/threrads on how to do it. Id spend $15 on the funnel it works great

 

^Hmmm. I haven't tried that, but I will tomorrow. Thanks for the tip.

 

Fans should come on at 212....whats your stock temp gauge reading?