Other than the obvious fact that these are not drilled for steam holes, do you guys see any reason why I couldn't use these (and drill the steam holes) on my 412 (4.185" bore).

http://www.summitracing.com/parts/SCE-011203/

Some how a miscommunication at the machine shop resulted in my pistons being .010" into the hole, rather than zero like I requested, so if I use a .039" head gasket I end up with .049" quench.

These are .032", so .042" quench sounds killer to me.

I'm not taking the short block apart, and paying to have it milled another .010", re-clean, and re-assemble.

-- Joe

 

Would work fine.

 

I wouldn't recommend a copper head gasket unless the block and heads are o-ringed or you're not running any coolant.

A good Cometic or MLS head gasket is much better and is still reusable.

 

Problem is I cannot find one that is under .035" compressed thickness and a 4.200" bore.

-- Joe

 

I wouldn't worry about it. A .060" over 400 block is really pushing it. You're trying to compensate for a mistake with a patch fix.

It's unlikely you'll notice a difference in power between a zero deck and .010 deck.

 

 

I'm not looking for more power. I'm looking to avoid detonation by keeping the quench under .045"..


Why do you say it's pushing it? Sonic test showed the cyl walls after boring were actually thicker than a stock LT1.. Block had no signs of core shift.

-- Joe

 

Cometic will make any thickness you want.

 

A single steel shim factory head gasket is only .018" thick but you're not going to find anything with that much overbore.

If you're that dead set about needing that "quench", rip the engine down and have it fixed properly. Why do you feel you're going to have detonation? If you get detonation, raise the octane level.

 

Short block is together, i'd rather buy special head gaskets than rip it down again. I'm not sure why ZERO got translated to TEN, but I've been using the same machine shop for 15 years so I'm not going to argue over it.

Octane is gonna be 92-93 pump gas. I want to get the quench under .045" because that's what it should be. Not .049" where it would be with a normal felpro 400 gasket. It's not su much that I'm worried about detonation as I don't want to worry about detonation.

This isn't an alky trailer queen, I need the car to work just as good on the street as it would at the track. Track only cars don't run at a set RPM up and down hills for an hour.

-- Joe