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What is the real world difference of an engines power band, given that they have equal displacements but different strokes?

For example: If you took a 4.25" bore x 4.25" stroke HEMI it comes in at 483", and if you took a 4.5" bore x 3.75" stroke HEMI it comes in at 477". All else being equal, ie same heads, cam, headers, intake, etc, would there be any difference in the dyno sheets? Theoretical answers are welcome, but do any of the engine builders have any examples of actual builds?

I chose the HEMI because it's not a suseptible to shrouding with the smaller bore.

IMO, there is a bottom line with everything and in this case, that would be ability to cope with the maintenance schedule dictated by rpm.

Pick the engine design you want to run, choose the desired rpm range you want to operate in.....this will help you determine the dimensions.

Personally, in a race application, I favor as big a bore as is practical within the bore space and enough arm to allow the cross section/induction side to reach my rpm goals. Do not overlook the mechanical advantage of launch rpm and gear ratios to accelerate a vehicle. It isn't JUST rpm, but useable rpm, including AFTER horsepower peaks. If the cylinder heads and induction can support BOTH icreased cubic inch and rpm, now we're talkin'.....but, there is the diminishing returns problem as engine size grows. Look at the hp per ci in NHRA prostock vs mountain motors. More overall steam for the huge engines, but look how much bigger they need to be vs their NHRA counterparts.

Advances in valve springs, rockers, lifters, pushrods, etc., have raised rpm levels without the associated carnage of just a few years ago.....although meticulous inspection/cycling is still required for elevated levels.

In a street application, where "low rev" seat of the pants and decreased maintenence are higher up the "importance" ladder, increased stroke will lower the curve allowing for more civilized gear ratios and converter flash, also resulting in fewer issues with valve springs, lifters, questionable pushrod angles, etc......

In your example of 4.25 x 4.25 vs 4.500 x 3.75 , I don't expect anyone would build two engines so different that "all else being equal" would ever apply.

Engines that radically different would need different build approaches to optimize its own internal dimensions.

I'd be racing the big bore combo and street driving the big stroke deal.....but that's just me.