Zero Deck Clearance

I want to build a budget 393 and all the dish pistons for this motor are very pricey. if I use a flat top 302 piston with 4 valve releafs and do not deck the block, will this give me a streetable compression with a 74 351w block?I was told to zero deck the block for better firing I think,can anyone tell me the benefit to zero deck? Is this needed for a street driven car?The heads I am using are cast iron with 64cc chambers.Thanks.

If you use a 3,85 stroke and a 5.965 rod and a 1.603 piston with 8cc valve relief’s like the H273CP with a 64 cc chamber .041 thick gasket 4.030 diameter and a .007 deck on a 9.5 block I come up with 10.81 to 1

If you used the 1.56 Chevy piston it would put you .050 down the hole with 9.84 give or take.

I’ve got nothing to do today so i hope i'm right
[img]/phpBB/images/smiles/icon_confused.gif[/img]
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Thanks for the info I was still wondering about the zero deck is this beneficial in any way? do you think 10.8 to 1 is too high of a compression in a street motor on 92 octain?Anyone know where to get a dish 302 piston thats less than 200 bucks?

By getting the piston closer to the head you create a tighter quench. The piston almost hits the head creating a rush or blast of the mix into the chamber. By doing this it keeps the chamber cooler and helps prevent detonation due to hot stops in the chamber. This will let you run a higher compression with out detonation. I think .030 to .040 is a good quench I maybe wrong getting old. My problem with the 393Clevor I'm building is it has no quench area the chamber in the head is wide open so I have to keep the compression down.

By the way I learned all this **** here at Ford Muscle.

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So I sould zero deck the block and get some dish pistons and be happy?[img]/phpBB/images/smiles/icon_lol.gif[/img]

So I sould zero deck the block and get some dish pistons and be happy?[img]/phpBB/images/smiles/icon_lol.gif[/img]

OOOPS[img]/phpBB/images/smiles/icon_eek.gif[/img]

So now we are going to spend some money [img]/phpBB/images/smiles/icon_eek.gif[/img][img]/phpBB/images/smiles/icon_eek.gif[/img][img]/phpBB/images/smiles/icon_eek.gif[/img] I would take the rotating assy along with the block to the machine shop and have them check all 4 corners of the deck using the rods and pistons you have. Can't go wrong that way. This will square the deck to the crank and put you wherever you want 0. Get a piston that has a -12cc dish and that should put you at 10.5 to 1
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Main thing with a zero or + deck is it helps control detonation
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This is interesting.
So, from a detonation control perspective, if you are targeting a certain compression ratio, are you better off going 0 or + deck height and using dished pistons instead of flat tops with a lot of deck?

Would the outer edge of the dished pistons create a better quench and turbulence?

In the past I would prefer flat tops for better flame travel. Live and learn I guess.