or how not to rather. I am trying to get a good idea of what my stock HG will hold in my '97. It seems from the searching i've done that everybody's has been different, but boost and timing have a lot to do with it. So if you've blown a headgasket please post what kind of set up you were running when you did it (mods, boost press, timing, etc.) Thanks guys. Kevin.

 

once with a 10 plate, 16* timing, and 3kgsk hx35@ 38psi
2nd with a marine gasket, studs, hx50 @50psi , ddp4's, 23* timing, tuned pump

 

Twice with the mods in my sig. the first was at 75 psi, second at 30, there better not be a third once i get it fixed

 

97 215 truck. 370's, #0 plate full forward, 12.5* timing, 42psi. ran it like that for a long time... went to 16.5* and the gasket blew at about 245k. pyro was burried countless times and the head had surface cracks on the face.

new truck will be run a little cooler

 

did you have to get a new head? were you drag racing a bunch or towing?

 

nah, they were just minor surface cracks. I think they came out w/ a .015 cut

but I spent a bunch of money on the head that's on this truck, and it's got narrower seats, so I don't wanna cook it!

no drag racing, just a toy for passing slower vehicles on the highway

 

268k 50 pounds of boost, 20 degrees of timing with a set of 370's, 215 pump with rack mods, and a pyro that had been buried a thousand times.

 

170k , 50 psi , 16.5 degrees of timing.

 

Seems like the head gaskets are kind of a hit or miss thing. Some of them hold a lot more than others. When i first put my SPS62 on i took it out for a spin and hit 51psi a few times but i decided to adjust the wastegate some just to be safe. Right now i can only hit 43psi but my head gasket is holding great so far. Timing is set at 17*. In the next month i plan on getting all my head work done. ARP 12mm studs, orings, and a marine gasket.

 

I have 240k on stock with 0 plate 16.5*timing and HX-40. Had the 1600 pyro buried on occasion and still good. I believe it is more drive pressure that kills them.....48 psi boost on a stock turbo is probably gonna have a good amount of dp. I'd still keep boost under 50psi no matter what kind of turbo/turbo's you have.

 

I agree with you on that one

I have ridden mine up to 60 psi a total of about 5 times now and its held up, I do know that they will hold bursts to 50 psi or so with ease if you retorque the head, as i have done, But i have reset my Blow off valves to pop right at 50 so that I can save that gasket a bit longer, christmastime is hard on the pocket book and now aint the time to blow that sucker up, goin back to 181s is in the near future too, till i get that head glued on..

Even so it seems these things can go at anytime at any boost pressure, i guess its a matter of luck... and so far, i believe ive pushed mine far enough...

Rick

 

First: Stock HG 375 marines, laser cut DVs, stock plate foward, star wheel maxed, 4k gsk, 22* timing

Second: Marine gasket, head checked to specs (was perfect), same mods other than the gasket

Both times the gasket was blown in between every wall and out the back

I made it about 5000 miles or less in between these two incidents, now i have the timing at 17* fire rings, and studs