Originally posted by Ducking_Fumbass
You aren't lifting the head, are you? 26 PSI is a lot to add to static compression...

Well, it's quite possible. Right now I'm having a hard time diagnosing the problem without taking the engine apart. Everything was fine- then one day during a hard pull at 20+ PSI, I noticed coolant had sprayed out the overflow and the engine started to overheat a bit. The water temp got to about 250 degrees so I shut it down.

I figured the thermostat had locked shut, so I installed a new one. However, on my first high boost run right after the install, it blew coolant out the overflow again. So I parked the car and assumed something was up with the head gasket.

Well, I took the car out on Sunday and boosted the shit out of it and everything was fine. At this point I don't know what is wrong and I don't feel like removing the head, so I'm going to keep getting on it hard until something breaks or I see more symptoms. I may check the coolant for hydrocarbons this weekend.

If anyone else has any insight, I'm open to your thoughts regarding this issue.