Hi everyone, I have a question about aftermarket head gaskets like Cometic, JE, GE, Supertech, Felpro, Cosworth etc.

My stock 2006 S2k blew a head gasket and the block was warped around .005" the machine shop doesn't remember how much material they took off, but they guess at least .008" I don't like using aftermarket parts, but .008" is the service limit from Honda (for a cyl head, they don't list a service limit for the block). So i'm right at the service limit if the machine shop is guessing correctly and if they took off more than .008" from the block, i have no way of knowing.

I can't afford a new block and couldn't find a used 06+ one either; plus my block is already put back together and installed in the car and just waiting for the head to go on (which has never been resurfaced and was checked to be straight). I know my timing is going to be off, but I'm going to 'band aid' fix it with a adjustable timing chain gear... I know it's not an ideal solution but timing geometry aside, I'm also worried about piston to valve clearance issues and really don't have the time to clay the motor; so I was thinking about using a .036" thick or a .040" thick aftermarket head gasket vs the .030" OEM gasket to get back some height/clearance... Yes, I know this is also not ideal, but it's currently the only option I have.

I noticed that most of the aftermarket head gaskets have a 88 mm - 89 mm bore and isn't the OEM bore size 87mm? Can these 88 - 89 mm bore head gaskets be used on a stock bore size motor, or are they for over-bored/sleeved motors only? Also, can they be used with OEM head bolts? I was looking specifically at Cometic's .036" & .040" thick head gaskets, which would give me an additional .006" - .010" of clearance, but at a bore of 89 mm, the bore size would be 2 mm bigger. What's the deal here?

I've also read about Cometic gaskets failing a lot in various S2K setups, but I don't seem to have any other choices. What's your opinion on the 89mm bore size gaskets - will they work with a stock 87mm bore? Should I just stick with an OEM gasket, but if I do what are the odds i'll have piston to valve clearance issues; especially in vtec? Has anyone out there had more than .008" material taken off their motor without piston to valve clearance issues?

I'd also like to hear about anyone's experience with Cometic or any other aftermarket head gaskets and their reliability. My search turned up a mixed bag of results and most threads were pretty old. Thanks.

 

 

Running a Cometic hg for 21000 k's now without issues.

 

The head wasn't resurfaced, so it's fine and measuring it won't tell me anything. It was the block that was decked but the machine shop doesn't remember how much they took off. I don't have the capability to measure the block. It doesn't matter now anyways because I just decided to go with a OEM head gasket. Thanks anyway

 

cool... nice to know for the future that cometic can be reliable. Is this on a stock motor, if not what mods?

 

Stock and NA but freshened up using some aftermarket parts. ARP head studs and bolts, and Supertech valves/springs/retainers.