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firstly define hi boost ? were your running head studs ? and yes what was the deck roughness like ? even though in the " race engine builders hand book " they say "the gaskets surfaces must be near polished, the problem is there must be some tooth to retain the gasket its a fine balancing act"

Even head gasket manufacturers state pretty fine Ra, ive seen anywhere from 50-60 RA or finer, some have even stated 15 or finer. The smoother the better, any protruding ridges from machining marks(noticed more so on rougher finish) will chew the gaskets as it expands and contracts, especially when its wedged between two dissimilar materials.

But as everyone else stated, headgaskets blow for a reason. Fix that issue and it wont blow again.

How did the engine fail? It wasn't from excessive cylinder pressure lifting the head, breaching the head gasket, hydrolocking a cylinder and bending/or throwing a rod?

My engine builder uses Nitto gaskets and has pushed them a long way without issue, maybe another factor influenced the damage.

People shitcan Commetic gaskets as well but we've run them without a single problem in boost apps exceeding 30psi. 26psi for 2 years straight racing.

Nitto are a better gasket IMO. I think you're missing something

People shitcan Commetic gaskets as well but we've run them without a single problem in boost apps exceeding 30psi. 26psi for 2 years straight racing.

Nitto are a better gasket IMO. I think you're missing something

As you would know, that's cos' people don't prep' BOTH the surfaces, and then they blame the gasket when it leaks?

To the OP, as has been asked did you prep' both the surfaces to the correct spec's?

yeah as above, most MLS gaskets are pretty stout and there may be another issue. but i've got plenty of experience using tomei head gaskets personally and never had a problem. they are very high quality and have lasted through plenty of heat, power and kms. I'm always happy using tomei.

yeah as above, most MLS gaskets are pretty stout and there may be another issue. but i've got plenty of experience using tomei head gaskets personally and never had a problem. they are very high quality and have lasted through plenty of heat, power and kms. I'm always happy using tomei.

I had a acl one fail straight away after a rebuild on my old 33. Ordered the tomei and it was gold.

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