Quote:
Originally Posted by Barnsnake
Personally, I think a big, broad stroker powerband is nice in a road car. For the drag racer that only runs below 6000 rpm in the staging lanes, the broad powerband is useless.
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You wouldn't believe what the stroke is on an 800ci Mountain Motor Pro Stock engine....
The cam (duration and LSA) determines the powerband.
For a street engine, my motto is go with as many cubes as you can get.
To get a 427, it's easier to go about it with an aftermarket block and crank, otherwise, you have to do a lot of machining to get exactly 427 with a production block. You either have to use an offset ground 400M crankshaft, or you have to bore the block out past .060" and use a 4.100" stroke. Even then you're only at 425ci. It's not "better" to have a bigger bore/shorter stroke, that's just the way it comes out with the aftermarket block combos. You guys shooting for the "magic number" have no clue on what you're missing out on with the larger displacements.
Think about it in terms of power per cubic inch. Builders often use that as a "benchmark" for determining how strong an engine is. A lot of my engines are in the 1.4hp/ci range.
If you have a 331 that makes 1.4hp/ci and a 347 that makes 1.4hp/ci, which is going to have the most power?
Keeping all other items the same, increasing the stroke will generally increase torque and broaden the curves.