Mech. comp. adjustments with head gasket thickness?

[drag-n-cuda]

Thinking about putting on Eddy 360 heads on 340 with flat tops above the deck. The 360 combustion chamber is a better design than the 340 open chamber to prevent detenation. Will have to use thicker gaskets to get proper piston to head clearance. Thinking Cometic or another thicker style gasket. Let's hear your thoughts.

Thanks,
drag-n

[ohioDemon]

dragncuda, i used a felpro marine gasket on my engine. it was .050 thick compressed i cant remember the p/n.

call felpro and ask them about it. just remember you want your quench to be around .040.
how far are your pistons out of the block ?

[drag-n-cuda]

I'll have to check myself, but the machine shop that rebuilt the engine said they were .008" positive.

drag-n

[skankweirdall]

.008 out of the block with a flat top piston? You can still use the .0395 Fel Pro. Mine are .011 out of the block with the Fel Pro gasket nets .0285 piston to head clearance. Using the small chamber W5's, milled .050 with 10cc's of valve clearance notch works out to 12.7:1 CR. The chambers measure out at 47 cc's. Yep .028 is enough with a steel rod. Believe it or not. Valve clearance is touchy as well at .058 and .078 with the lash.

The edge is the only place to live.

[drag-n-cuda]

skankweirdall,
I've heard that about .038"-.040" is about optimum, have you heard this? I realize you "live on the edge", but I'm not that brazen. Would like to be slightly conservative on my street/strip (bracket) car.

Thanks,
drag-n

[rumblefish360]

I was running those numbers.
Zero deck and Fel-Pro's .039 compresed gasket.
OPen chamber J head.
MoPar create short block w/.011 positive pistons w/Edel. heads used a Fel-Pro .054 think gasket.
I haven't gotten closer yet. But it's enuff comp. for the street for me.

[Locomotion]

Another gasket you may want to consider are ROL High Temperature head gaskets. HG31030HT for small blocks.
They are .045 compressed and have sealed much better than the Fel-Pro 1008 for me for years!

ROL homepage
Gasket material info
Specs

[skankweirdall]

drag-n-cuda, yeah, I've heard that as well. CRE down here sets up all his engines with .038 quench.

rumblefish360 , yep I used a Mopar crate short block because of time constraints and that's how it came out. I figured it would either work or bang the hell out of the pistons tops. I've never had a problem though.

A few years back I remember reading an article about one of the Mustang nitrous racers and his engine, he said you could actually see where the pistons touch the heads. He didn't say what the setup clearance was though.

[cuda66273]

.035 as the minimum on our 318 with closed chamber heads we set the head gasket at .036.

This is with a stock rod, different rods require different clearence's.

Always check with the rod manufacturer