f-bodman

So what head castings have the "notch" that you can't run with the MLS gaskets? I don't really know what this notch looks like. I have 862 casting 5.3's and was worried about a coolant leak with the GM MLS gaskets.

bigdsz

iTrader: (1)

I don't think the notch situation applies to heads other than '97 and "98 LS1 castings. The 862 5.3 L castings are later production. I have been running OEM graphites with those castings, and was forced to do so again yesterday when my heads were reinstalled. I really wanted the Cometic MLS .045 to get my quench at .038 but could not locate any for love or money. Cometic gasket non availibility has got to be costing Cometic and our sponsors a pretty penny.

f-bodman

Thanks for the reassurance. I might go with cometics yet, depends on what kind of p/v clearance I end up with. Why would you go with the .45 and not a .42? I was also asking because I just helped a freind put 853 castings on his car and he used the GM MLS gaskets.

bigdsz

iTrader: (1)

The MLS gaskets are thicker than the graphite gaskets. I have never measured them, do a search. To determine optimum quench you must measure how much your piston is out of the hole, generally .005-.007. Deduct out og the hole measurement from gasket thicknes and that should be between .035-.040. FWIW the .042 Fel Pros have a tendency to blow. Cometic though way over priced are theonly way to go.