[CraigG.]

Hey everybody,

Would one ever go, less than zero deck (piston higher than deck) in order to raise compression?

I have a stock block '72 455 at a .040 over, Ross flat tops, stock length crower rods, stock 455 stroke, 72CC early E-heads cut .060 with 2.11/1.66 vales and Fel Pro 1016's .042 compressed.

Thanks Again, CraigG.

[WDCreech]

I ran pistons .005 out in one engine, but the pistons were, just, kissing the head, so I insalled thicker head gaskets. Problem solved.

[TIN TIGR]

every hot motor i do is above deck..just did an olds 455 thats .020 out..gobs of compression..

even with our aluminum rod small blocks, i go out..if the pistons dont leave a shadow on the quench at 8000 rpm, you're a pansy..

always run zero deck minimum..every stock class racer i ever talked to ran .005-010 out..

[mechanic17]

Dude, aren't you already at like 11:1 or higher with that setup?

[slowbird]

If your heads really are cut .060 then you compression should be over 13:1 now, just how much compression do you want? I dad's engine is either .005 or its .010 above the deck, I just cannot remember which it is right now.

[CraigG.]

Hey Brian, Dude and Everybody else, I'm running E-85 and others are able to run 15 to 1 NA. I don't have a stroker so I think that I am at more like 12 to 1. I am also not sure that it was a full .060 cut it might have been more like .040. Thanks Again, Craig G.

[slowbird]

Then mill the heads more. It would be cheaper and easier. You should be able to get them down to about 58cc to 60cc chamber volume. Then if you want more mill the deck and put the piston out of the hole .005. Although I dont think raising the piston out of the bore will give you more than a quarter of point in compression it will give you some. Milling the heads is your best option for getting a good increase in compression. Or get dome pistons.

[INJUNTOM]

My other 455 shortblock is set up for .005 out of the hole with SRP pistons and billet steel rods. Used a Fel Pro .042 gasket, and no signs of touching when I pulled the heads.

I think the main reason for bringing the piston out is more for quench purposes than the very small amount of compression you may gain...

[gtome]

I couldnt bare the thought of turning more off the block or e-heads....that cant ever be undone. Id go for domed pistons!

[WDCreech]

Originally Posted by CraigG.

Hey Brian, Dude and Everybody else, I'm running E-85 and others are able to run 15 to 1 NA. I don't have a stroker so I think that I am at more like 12 to 1. I am also not sure that it was a full .060 cut it might have been more like .040. Thanks Again, Craig G.

Craig, Go ahead and mill your heads to a full .060, but be sure to mill the intake side, also, to keep the intake match. Both of my engines are at just under 16:1, and I run 115 or 116 octane race gas, depending on which method of rating is used. Be forewarned that my first 474 started splitting when I had a factory block. Factory offset ground crank, Eagle rods, and JE pistons, shifted at 6600 and went through the traps at 71-7300. I now have an IA block and a forged crank. My 606, with a tall deck IA block, has a 5" stroke billet crank, MGP 7.07" aluminum rods, and JE pistons, is shifted at 7600 and goes through the traps at 81-8200.

[OINK 1]

I've done them @ .015" sticking out. Then I'll run a .039" crush head gasket.
No problems !

Pontiac Gregg

[Mike S]

Mine are .007 out. My heads are not milled. Last time I had the heads off there was no carbon what so ever on the flat part of the head. No flame getting there. I am running a .039 head gasket. I have had the block line bored twice and milled once. I was thinking of milling my heads to get more comp. Decided to stay at 12.0. After all I am as fast as i can go for now in the car 10.00

[TIN TIGR]

oink, quit being scared..run those pistons tight against the head..lol

[Skip Fix]

So how close are you guys running that see kissing?

[CraigG.]

Hey everbody,

What about this FLAME TRAVEL Issue on the Quench part of the head?

Dude, Tom V., Paul Spotts - Other Builders that I can't think of now - No Disrespect Intended.

Thanks Again, CraigG.

[CraigG.]

Hey Slowbird,

The motor is a start over so I have to deck any way.

Thanks, CraigG.

[CraigG.]

Hey Everybody - Thanks!
CraigG.

[68birdfreak]

I am running mine about 5 thou outta the hole on the 461. milled the heads i believe about 80 thou.. hoping for 13 to 1 give or take