Cometic MLS Base Gasket for Porsche 996 & 997.1 turbo

What size are these?

The Cometic MLS Base Gasket for Porsche 996 & 997.1 turbo are for 107mm spigots.  This is the OEM size liner base, so these will fit 100 to 102mm liners that are slip-in.   We can make our 103.6 piston cylinder kits slip fit on special request.

These are 0.027″ thick like the oem base gasket on 997.1 turbo and a little thicker than the stock 0.010″ thick 996 turbo base gasket

These are designed to fit oversized head studs.  7/16″, 12mm and even 1/2″ head studs.

Why can’t I use OEM base gaskets?

If you’re building your engine for high power you want to use the best base gaskets available. Cometic has made a tremendous name in racing and high powered street engines with their MLS base gaskets.

If you’ve put in big head studs, you’ll be needing these.  OEM base gaskets are about impossible to drill out and oversize.  Save shop time and excessive labor by purchasing the correct base gaskets for your build.

Can I use these on a stock engine without big head studs?

Absolutely!   Even with a stock engine build, these base gaskets are a nice upgrade for improved sealing over oem head gaskets.

On 996 turbo’s you can enjoy a slightly lowered compression ratio like the 997.1 Turbo has for a bit less knock sensitivity.

how many do I need?

These are priced individually, so you’ll need 2 if you’re doing a full build, or only 1 if you’re doing a single bank repair.

Need help with your build?

Check out Protomotive Engine building and Protomotive consulting service.