BBF - flattop pistons and 90cc heads, or dished pistons with 76cc heads?

I asked this on the 385 forum, thought I'd throw it out here too:

Which is better? My goal is to run on pump gas, 92 octane, make 450 hp and over 400 ft/lbs of torque (more if this is possible) to drive on the street. Until I can afford to fully rebuild the engine, the plan is to obtain a running engine (I have a line on a truck 460), re-ring it, slap some worked over factory heads, stealth or RPM intake, 230/240 hyd cam, headers, 950 BIGS holley and drive this sucker on sunny days and warm nights. AND hopefully turn low 12's (high 11's [img]/phpBB/images/smiles/icon_biggrin.gif[/img] )in the quarter.

This leads back to my original question: obviously if I don't change pistons in the truck engine, I'll need to go with DOVE heads with the smaller chambers to get the compression up to a decent level (say 9-9.5:1). OR would it be better to go with flattop pistons and a pair of the larger chamber heads? Are the larger chambers prone to detonation? I'm a cleveland guy right now, and I know you can run pump gas with the closed chamber heads, due to the "quench" design. Can you do this on a BBF also?

Thanks for any help, this is a great site with VERY knowledgeable people!!

Pat

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With D0VE's, I'd run the dish piston and with the open chamber heads, I'd run the flat tops.

the flat top's with D0VE's would make over 11.5-12 cr.
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Small chambers and dished pistons are usually a good combination for efficiency and minimal detonation.

You'll have less of a detonation problem with the smaller chamber
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Id go with the smaller chamber and dished pistons. I've been told by several people you'll make more power this way, even if the compression ratios are the same. Think of it as being like a boattail'd bullet. Focuses more of the combustion energy on the center of the piston, instead of on the rings, where some (depends mostly on the build) pressure will bleed by.
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I had a 9:1 472 that pinged like a mutha' with D3 heads and factory dished pistons. I think a key is your cam selection. Too much overlap and low compression is a bad combo. Good luck.
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The chamber design on the D3 heads is just made for detonation! I've ran several cams with the D0VE style heads & the dished pistons with no problems...
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I am reading this with interest because I have a 460 with D3VE heads sitting on my engine stand.

I have seen D3 heads recommended on this board because they have (I'm going by memory) the same shape closed chamber as the D0 heads with the roof raised .100" to create the larger chamber. According to the way I remember those posts, the recommendation was to use flat top pistons and mill the D3's to the desired compression ratio. The result is supposed to be a custom sized chamber with a detonation resistant design.

Can I assume those of you that have answered this post disagree? I thought the D2VE was the only open chamber 460 head. Do I have my facts wrong?
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tim1859, I share your point of view. The D2VE are definitely open, and are reportedly very prone to detonation. The D3VE is shaped like the D0VE head, but it has a 92 cc or so chamber, as opposed to 75cc.
From reading the 385 board, I have gathered that the deck clearance has a big effect on detonation. If the piston is down in the hole, then you lose the quench effect and get detonation. Some guys there report running the D0VE heads with flat-tops on pump gas by zero-decking the block. The zero-deck gives the quench, and a cam with considerable duration/overlap bleeds off some compression.
I'm planning on zero-decking my 460. I'll run D2OE Police Interceptor heads (88 cc) with KB #137 flat -tops and a 230-ish cam. I'll be a lot closer to 500 hp (if not over it) than 400 hp. And I hope it will run on pump gas[img]/phpBB/images/smiles/icon_confused.gif[/img]
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I zero deck all mine except my race engines which are usually .020 out. The zero deck is a definite plus especially with a flat top. The biggest gain you'll get is cleaning up the chambers & cleaning around the exhaust valve.
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