We ONLY deal with cometics for Pontiac V-8's!!!! Cometic MLS (Multi-Layer-Steel) gaskets are viton coated stainless steel cylinder head gaskets, now available for traditional Pontiac engines. They offer superior cylinder pressure sealing and water control for demanding aluminum head to cast iron block applications and are unique in that gasket thickness can be varied to allow fine tuning of compression ratio and piston to valve clearance.
Gasket Instructions: Install on clean dry surfaces using no sealer of any kind. Torque to manufactures specifications, re-torquing is not required. If re-torquing allow engine to cool completely to ambient temperature. Gaskets can be reusable until spring embossments lose their memory (avg. 4-5 teardowns). HOW TO ORDER:We need to know the following 3 options to order the gaskets:
SPECIFY BORE SIZE
SPECIFY WITH OR WITHOUT CHAMFERS(Block chamfers are also known as scallops - these are slight cuts at the top of the deck for valve unshrouding). "MLS" stands for Multi Layer Steel, the Cometic gasket is comprised of three layers of steel, outer layers are .010" thick embossed stainless steel coated with viton (heat resistant to 482 degrees Fahrenheit). The center layer is also embossed and it's thickness can be varied to control the gasket's final "compressed thickness". Pontiac Cometic head gaskets are available in: .027", .030", .036", .040", .045", .051", .060", .065", .071", .074", and .120" thicknesses(.060" and thicker are four layer gaskets). Cometic MLS gaskets are reusable and ideal for the shearing forces created by aluminum heads on cast iron blocks, they do not crush or require retorque. Another great feature of the MLS gaskets is their ablility to promote a even load across the sealing surface resulting in reduced cylinder bore distortion. Cometic MLS gaskets have been successfully used on Nitrous, Turbo, Superchared, and Natrually Aspirated Pontiac engines. The smoother the block and head surface the better, Cometic recommends a 50RA or finer surface finish(try to find a machine shop with stone surface grinding machines). They are installed dry with no sealers. Ordering a set can get a little confusing, here are most of the options available:
Bore sizes possible 3.750, 3.975, 4.160, 4.200, 4.220, 4.240, 4.250, 4.260, 4.265, 4.270, 4.295, 4.300, 4.360, 4.380, 4.410. Round or with valve pockets(either option is not available in all bore sizes at this time call to be sure). Expect delivery of special orders in 3-4 weeks(wait may be longer during racing season) also available are small water hole and no water hole gaskets. The gaskets are not designed for 421, 389 and some 400 blocks with early style valve reliefs (1967 and earlier valve reliefs are wider and in the 8 O'clock and 4 O'clock position).
Compressed thickness from .027" to .051" - $194.00 pair Compressed thickness of .060" & .065" - $242.00 pair Compressed thickness of .071" & .074" - $242.00 pair Compressed thickness of .120" - $438.00 pair The gaskets are currently being used by several racers and street car customers with perfect results. One customer has the cometics on a 871 blown pontiac, one customer has a 13 to 1 naturally aspirated, and one customer has an engine used for pump gas having the cometics used to lower compression. All 3 of these customers run coolant with 0 leakage. The cometics allow deleting o-ringing blocks and heads, but for those who prefer o-ringing and copper gaskets, we still offer that option. Related Links: