Cometic head gaskets - NJFBOA - Home of New Jersey's Camaros and Firebirds

Blacdout96 · 10-25-2011, 02:46 PM

Anybody run a set from them? any pro's? con's?

Looking to get a set for my 3.8 project. Original head gasket thickness is .062, and am looking to go .051 ( 3-layer), .052 or .045 ( 4-layer). Not sure If I should go with the 4 layer and play it safe, or go 3 layer to maximize my compression ratio ( my goal was to shoot for 10:1, or as close as I could get)

What's your thoughts guys?

Blackbirdws6 · 10-25-2011, 03:58 PM

You going with a MLS or some other material?

Blacdout96 · 10-25-2011, 04:07 PM

Yes, here's a link to the info for them:

http://zzperformance.com/grand_prix/...1287&catid=103

Pampered-Z · 10-25-2011, 05:18 PM

I run them.

READ THE PART THAT STATES: According to them a 50RA OR FINER finish is needed on the head for proper sealing.

This means you need to make sure the block and heads are finished to this or you could have sealing issues. People have not done this, and with high compression ( boost/nitris )had to tear their engines down to get them refinished properly.

Blacdout96 · 10-25-2011, 05:24 PM

Yes, I'm resending my block out to my machinist to double check that. the last machinist I took it to looks like he cut it too rough.

Any particular reason why you chose to run with them pampered?

Blackbirdws6 · 10-26-2011, 07:05 AM

Quote:

Originally Posted by Pampered-Z

I run them.

READ THE PART THAT STATES: According to them a 50RA OR FINER finish is needed on the head for proper sealing.

This means you need to make sure the block and heads are finished to this or you could have sealing issues. People have not done this, and with high compression ( boost/nitris )had to tear their engines down to get them refinished properly.

^^^What he said. I run the 3 layer MLS from cometic and everything is working well so far. It may be a bit overboard for what you are doing and since these are picky, you may just want to save a few bucks and go with a good quality regular head gasket.

Pampered-Z · 10-30-2011, 10:57 AM

After getting everything together = Zero decked block, custom pistons and cam I was at 9.8 CR and and my PTV clearance was a bit tight for a stick car. so I needed a thicker head gasket, I went with Cometics .60.

Blacdout96 · 11-01-2011, 02:08 PM

One of the tricks I heard to get them to seal a little better is to actually drill out the rivets, and seperate the layers. There's apparently alot of machining left overs between the layers, and you have to wipe the hell out of them to get all the crap built up off of them, heard very few blow outs occur after performaing that.

Pampered-Z · 11-04-2011, 09:02 PM

Quote:

Originally Posted by Blacdout96

One of the tricks I heard to get them to seal a little better is to actually drill out the rivets, and seperate the layers. There's apparently alot of machining left overs between the layers, and you have to wipe the hell out of them to get all the crap built up off of them, heard very few blow outs occur after performaing that.

Yes Cometic "should" include a paper with the gaskets that explin that you need to test fit and if needed remove the rivets. Um, they forgot this when they sent mine. And the rivets WILL CAUSE ISSUES WITH LT1 ALUM HEADS... So once the filled the coolant I found a nice little drip down the side of the block. I had to pull it all apart to cut the rivet off.