I've got a 03 LS6 block with dished pistons (should be about 9.2:1), stock 243 heads, ARP head studs, and a maggie at about 9-10lbs. Which head gasket should I use? What thickness? Cam is LG G5X1 228/232 .588/.574 114

Thanks

 

Cometic .051 gets my vote over .040 so you won't have a compression increase, especially w/ boost. Spray some Permatex copper gasket on it and you should have no sealing problems.

 

Cometic .051 here, 12#'s of boost, and no problems.

 

I'd go with a .040 cometic to increase compression a little. Maggies like compression.

 

+1 on the Permatex Copper coat spray.

 

Thanks for all the suggestions guys!

 

Who cares on the thickness, I just want the chic in your avaitor! No, but all kidding aside, the cometics @.051 will do the job just fine for you and use a ARP head bolts as well.

 

I, actually put a vote in for the GM MLS gaskets. They work great, and are not so finicky with the RA smoothness of your deck and heads. IF you are NOT getting your deck AND heads both resurfaced to at least a 200RA finish (close to a mirror finish), don't even bother with the cometics. They will leak and the copper spray is just a band-aid to the problem. Go with the GM's and be worry free.

 

And above all, it must seal well! The stock MLS gaskets have a good reputation in this regard.

FWIW, I think you could afford to increase the compression a tad. But the 0.040" gasket might have a more significant effect on quench. Will it be too tight for FI?

I would check with the other guys running similar set ups and see what they are doing and how it's worked. Or check with the vendor that's been selling them. (Is it MTI?)

 

not to steal this thread but how much of an advantage is the MLS gasket over the original graphite ones? I have 806 heads with the notches and understand you cant use the MLS ones? I am trying to see if it is worth welding the notches and resurface for the MLS's. Thanks

 

I use the GM MLS, on my 418cid, with copper spray and i run 11.9.1 and 300 shot of nitrous and ARP studs and never had any problems at all.