04 5.3 BTR stage 2 truck cam, first a set of 241 heads milled .015 (came on truck when purchased). Drive for a few thousand miles, started pressurizing the cooling system. So I had another set of heads sitting there, swapped those heads, gm head gasket, reused the arp head bolts, drove fine, went and had it re-tuned... made it maybe a week after and popped another. Any suggestions?

 

What are you torquing them at?

 

What's timing at?

 

Has it been overheated in the past? Maybe the deck isn't flat.

 

The Blocks aren't truly flat from the factory. Your's is likely out of spec.

 

Torqued to 75 per ARP instructions

I couldn’t say if it has or not been over heated in the past. I know since I’ve owned it, it hasn’t been. I caught it before it got too hot.

Timing is at 26*

the deck not being flat is what I was thinking... not exactly what I wanna do lol.

 

I have 1 block in my garage like that and I have done head gaskets on 2 other motors like that.

The one in my garage has a low spot in the middle on one side of the deck. It also has a core shift issue to one side. It was decked on one side and was clean. when they went to the other side, they had to drop the milling head to reach the deck. After they skimed it you could see it had a low spot in the center of the deck.

One of the vehicles I repaired a head gasket on had coolant leaking out in the front between the head and deck. The head gasket was just replaced prior to me doing it and It seemed odd and we just assumed the gasket may have been defective or maybe they didn't have the head surfaced. It wasn't till after tearing into it and checking the block surface in several areas that we discovered some low spots.