^ Very true. This is nuts how often 3mm are going out these days. My 3mm was great at 17-18 psi daily with no issue. The second we went over 20 psi, there she went. Now that the stock HG is on, she's great!

 

Yeah, about 500 whp on pump gas is about at the limits of the fuel no matter what HG you use. Its not the 3mm HG's fault, its pushing the limits of the fuel that causes the blown HG over time. If you were running race fuel or e85, and pushing 26 psi of boost, you wouldnt have the HG problems youre having.

 

Chadd.... it happens. Your clock is ticking as well

 

log mani + 26 psi + 3mm hg = eventual boom.

if he was ELTM i bet it woulda made same power on less boost, and not blown. remember, he had to crank up the boost becuase of that log mani.

swapping in a 2mm wont fix the problem. lower the boost, or go eltm like you planned, then i bet you will be fine.

i am not a fan of teh 3mm hg, but i have to admit if used properly and not pushed it should last.

 

Doesn't suprise me, the same happened to me. I got a good 15-20k out of my headgaskets when i kept the power around the 500whp mark. I have since gone back to stock compression and am making around 450whp on much less boost and 12psi. For my street setup though its way more power than i need anyway, but if you want the power, just replace the gasket and do it again, only maybe lower the power a bit.

 

Yeah I am switching to ELTM at the same time of fixing the hg issue. I'm just unsure of going the 2mm route if it has less problems. I want to do a bit more research first though...

I agree it took more boost to achieve the 500whp mark on the log but I was hoping the hg would last a bit longer than it did. Oh well I'm not mad it's just part of the game

 

If you're thinking 2mm consider the SCE copper gasket has built in O-rings.

 

Leaking valve seats will cause air to go back through the intake and out the open valves in other cylinders.

 

See though...I've had two IP 3mm HG's with ARP headstuds installed properly and have pushed them both very hard (25-30 psi; 550-700 whp for 3 years and about 5000 miles) and havent blown one, but I have also always run race fuel and e85. The only reason why I'm now on the 2nd 3mm HG is because I pulled my head after the first 2 years with it to build the head.

Tom at IP also runs the 3mm HG on race fuel and has been for a while making around 740 whp with no problems.

If you push the limits of the fuel, any HG is going to blow eventually. Its not the HG's fault, its the limits of the fuel being pushed and detonation and heat being present.

 

^ I think the heat being present is what was the death of my headgasket. The log simply creates way too much heat at 26psi! It cooked the ceramic coating right off the manifold and the hot side of the turbo.