Ok, I know that overflowing coolant can mean a blown headgasket. I also know that white mily **** on the oil cap or in there if you look can mean a blown headgasket.

What happened: While tuning tonight the car overheated. Coolant was up to the "max" level on the overflow tank and it was bubbling and ****...some bubbled out. We let it cool and in the process I looked in the oil cap area. I couldn't see any milky fluid in the head...buuuuut I did notice a thing coating of white bubbly looking fluid on the underneath side of the oil cap. (my heart sunk right then). This was not during a WOT pull.....it was on a mustang dyno and they were tuning driveability so they were just doing a constant pull at around 4000ish RPMs

Question: how likely do you think I have a blown headgasket? Could this just be a scary thing that happened tonight and things are fine? The car is not overheating now and normal driving shows normal temps. Everything seems to be normal as far as temps go...and the overflow can is not getting full or anything. We also made sure to watch it carefully and shut it down when the temps got above 215. There was just no air flow in the place and its 88 degrees here right now.

Info:
- The motor is a fully built ls/vtec
- 84mm
- cometic 3-layer headgasket
- everything was machined flat and good to go
- the motor had 622 miles on it when it went in for tuning....it came out of the shop with 643. So the HG is basically brand new.

I am going to get a leak down test done tomorrow, but I just wanted to get this off my chest because I can't sleep right now because of this....it's ******* killing me.

 

Oh....and I don't smell any coolant since that happened. We also pulled the dipstick and the oil on it looked like what oil should be (Smooth, fresh and....oily? haha)

 

On the Mustang dynos you can do a sweep test and a step test. The step test is what it sounds like you guys were doing at the time. But in order to do that on the Mustang you have to set the RPM speed with the car. But anyways, sounds like the head lifted on you. So there is a chance that you will not see that coolant doing that until you get more high boost WOT throttle dyno pulls and/or street pulls under boost. The HP cometic are not as good as the standard, and the OEM one. Check with Golden Eagle, they sell OEM style ones that seem to work excellent. Be sure to recheck your studs or bolts to make sure they are torqued correctly.

Good luck,

Jason

 

you think its possible for the head to lift with ARP's? And <U>if</U> it did lift, what complications could that have caused? Could it just lift and thats' that...just retorque and it might solve the problem type thing? I guess I'll have them retorque them as well.

 

It's possible for the head to lift with just about anything. There are tremendous amounts of cylinder pressure. No, you will or I would suggest that you should change that head gasket.

Good luck,

Jason