[cobrashoch]

1blackbb66 - on production 385 engines some general observations. My 0-deck flatop piston .0030 over engine w-9 to one slugs could only fit a 6.7 rod in because a 6.8 rod pin would get into the bottom ring. Depends on the pistons design you order I guess. A 4.5 crank is about the most you can run in a production block and on the bore side of the block the less you bore it the more efficient the rig seal will be from block flex. Yes I have heard about 4.5 bore jobs but that's only under certain conditions, and usially for racing engines. A excellent combo would be a 4.3 stroke at no more than .0040 over. Even w/mild headwork you will be well north of 600 ft lbs of torque. And there in lays the secret of 385's, in street trim they ALL make about a REAL 600 lbs.torque. But (as they say there is always are butts) all things being even, as the displacment goes up on 385's the torque curve moves down, and become more flat across the rev range. Also,for every 50 cu.inch. you put into the engine from 429 cubes you will need 6 to 8 degrees more cam too, or it will loose horsepower. And for heavens sake keep your lift in a street engine to about .65 lift. and invest in aftermarket rods. You can run more lift but trouble free miles goes away in almost all cases,,,,,, (flame on)
Forget all that rod angle jazz because even the stock 6.6 rod lenth is really o.k.for a 4.5 stroke, though the longer rods will give you a tiny bit less side loading, but not much really. My old mans dump trucks prove that to the tune of 200,000+ miles. So the bottom line,,,,,, both torque and horsepower numbers will stay around 650 numbers on most street 385 builds regardless of displacement and rod lenths. The major difference is how hard it will pull and how hard you will have to push it to get there, and that effects how reliable your engine will be. You won't believe how hard big cubes pull AND how fast things happen too.
cobrashock