Idk but the second time it blew it had a brand new head and a new set of head bolts.

 

I suspect a quality of workmanship issue there, but that's real easy for me to say from here.

 

Nope not one but mechanic for over 50 years did it. The guy builds his owne motor, does his own bodywork and paint, all fabrications work, and wiring.. he grinders his owne valves bores motor balances them. Truly one of the best their is ok this planet. Hands down. And I will put my life on that.

 

Sounds like you put a head's life on it, and it didn't survive the bet.

 

Even the best screw up is what I'll say.

I build condos and apt buildings, and even I pound the occasional nail wrong.

 

The bet was that the job was done right as it was and while I assisted. Simply had to do with high boost pressures simply as that.

 

That's not high boost. And simply will not pop a head gasket at low stock timing. Period. Not a properly installed one. I had a he351 with unknown timing probably a bit more then stock on a stock hg truck with 4gsk and tuning. Wastegate plugged, I could hit about 40-45 psi which in a he351 is like 60 or more psi of drive pressure due to the ultra small housing. Far smaller then a hx35. The head gasket leaked coolant the whole time I owned it until I studded it. Raced the truck all the time against imports and stuff. Defiantly wasn't nice to it. Didn't pop it. Probably leaked coolant for 10000km. 45 psi isn't high. There's guys running 80 psi on stock bolts and gaskets with below 16 timing and they last. Not about boost. It's about timing. There's tons of guys on here running 16 degrees of timing, a bunch of tuning and small mods on a hx35 at 35 psi on stock hg. The 5 psi difference won't pop a head. These aren't 6.5's

 

I... no, what he said. ^

 

I just don't get, on an engine that runs 500psi of cylinder pressure, and 17-23 psi out of a turbo as well; which will regularly last past the oem service life (320,000 miles) by hundreds of thousands of miles, anyone really thinks an extra 15 psi is going to murder it.

I mean, the shops here advocate doing HG and studs when you exceed what an hx35 can reliably do, because no one who ends up with another turbo keeps the stock timing and keeps that 35psi. They always get more. Always.

 

Ya it just doesn't happen. You just had bad luck. Or poor workmanship. That's all, I always suggest studding, valve springs, head work, and perhaps o ringing although not totally necessary to any 12 valve owner. Everyone wants more power, more rpm, etc and doing those things all at once will open up a whole world of performance. Anything else to me is just being cheap which never works out in the diesel game. Studs are always worth it, I went with 625's so I knew I could reuse them and the investment wouldn't be lost. Used them on my old engine and reusing them on my fully built new engine.