Depends on what "tall deck" you have to work with... and what sort of build your going for.
Our wallets are definitely different sized. I say the same thing about the 10.2 block with standard cam bore and .842 lifters :redface:
eh
I didn't say it wasn't expensive, it just gets $tupid after that.
If it's a used (seasonedPriced out parts for 565 build ..looking at about $6500 without cam & lifters for rotating assy, block , and ring set Dart Block ,Howards Crank ,Oliver Rods and Ross pistons , ......454 parts using my block will be about $4500 less machine work to bore and prep block again really torn to go tall deck but then looking at new pan , blower intake, pushrods ..yaddayaddayadda
) Chevy block (not a Bowtie) personally I wouldn't use it. If you do use the block, plan on helicoiling/keensert every head stud hole now while it's apart. If not, it will strip eventually and likely when you least want it to.....I don't understand what you mean "Seems like the longer stroke motors use up cylinder head at a pretty low RPM". Could you explain?
Piston speed.
What kind of rpm Scott and I assume this is drag race use and not endurance stuff. What kind of top end and compression are you needing for 1200hp and how many passes before inspections/freshen ups?
The higher piston speed require larger heads with more flow to keep up. The rod/stroke ratio on a standard 9.8 deck 582 is going to require a head with some CSA to turn 7500rpm.
Big compression, and a spread port top end would make it easier but there are conventional heads these days that will do it. RPM would depend on induction but it could be made as low as 7000-7100 with very broad torque. Endurance or drag would again depend on induction and rpm range. Not many endurance engines run TR's but a stack injection would sure work. Laps/passes/maintenance would all depend on how well the engien was put together. KJell Adams has a 572 (4.56 x 4.375) with some small Dart Big Chiefs, sheet metal intake, 2 x 4 Dominators, I think it had ~14:1, a Straub solid roller that was (I think) under .800 lift and it made 1165 NA in the 7000-7100 rpm range and ran for several seasons (and they ran a good amount of Nos through it to). From what I understand they never even had to adjust the lash. :dunno:
If you used a piston with the same pin height and had a custom rod made, the difference in ratio between a 496/540/565 and a 582 is ~.05:1 (basically the same as a 572/588 tall deck) which for all intents and purposes is negligible but I think most guys just move the pin up in the piston a little and use the same 6.385 rod. Then it's only a difference of about .04:1. They're all a little short but most guys use heads that are too big anyway so it usually works out.
The stock rod ratio on a 454 is only 1.53. Look at the ratio of a 632 with a 6.535 rod. Even in a tall deck it's 1.37:1. Now THAT needs some cyl head to turn some rpm. Also, there is a difference between turning 7500 and making peak power at 7500.
In most cases these days I don't see the need for spread ports on engines making power in the 7000rpm range. if you're trying to make power in the upper 7000rpm range, then they become a consideration but with the conventional heads on the market today you can do pretty darn well without the spread port stuff. In the case of the 572 above, it's what the customer had (the heads). I think he was originally starting with the idea of a 4.25 crank and was advised to add some stroke to help "use up" those heads since he was trying to make power in "jet boat" rpm range. I think a pump gas version even with a wet sump should be able to make 1K hp. I know DNE did a 565 pump gas deal years ago with a single four that made 1K hp and things have changed almost exponentially since then.
Displacement is always your friend. I'd do the 572 (4.56 x 4.375) but remember that the more stroke you have, the more windage becomes an issue. A dry sump would be really nice on the 572...almost to the point where I'd say if you don't want to go to the expense, then stick with the 565. The key to any engine's potential is the induction. Heads, cam, intake and exhaust are all going to need to be thought out as a combination based on your engine's displacement, rpm, and how much power you want to make.
