I have done some searching and found people split on Cometic gaskets. When I checked Felpro and TFS both make a MLS gasket like the Cometic. Are these gaskets as particular about finish as the Cometic MLS? I was hoping for a thinner than stock gasket for a compression bump, but I'm only changing heads, so I'm worried about the block surface.

 

For the price difference between Cometics and stock GM gaskets, it maybe cheaper to have the heads milled to achieve the same thing. Around here is costs about $75 for the pair to have them milled.

 

Very good idea, thanks for the info!

 

Thats what I did, $90 to cut the heads and I just bought a GM head gasket/bolt kit from LPE

 

The Felpro 1041 is a composite gasket that works fine for NA, with even a little power adder, (up to 150 shot) measuring .041" thick compressed. It is not as finicky as a MLS gasket either for surface finish. The price ain't too bad either.

 

If you use a composite gasket, and you change your heads be prepared for some major cleaning of the deck surface. MLS are a much better choice IMO as they require less clean up if you have to remove them.

 

I was planning on running a 150-200 shot. I don't mind doing prep work, just don't want to pull the motor to have to mill the surfaces.

 

I'm going with LS3 gaskets on my 403.. they are .051" 5-layer MLS... they are supposed to hold up better than the LS2 3-layer gaskets do (not saying the LS2 gaskets are weak cause they arent!!)

 

Only if they are 'graphite', not composite. Two totally different non-MLS gaskets. Graphite was OE on older LS1's, GM never used composite head gaskets on these engines.

 

Learn something new everyday!