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EXACT same way, it WIll make more power.....it's not an opinion, it's simple physics.....not that hard to figure out really.


Dave

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It may be physics..... but far from simple.
Bearing speeds/loads
Ring friction
Rod/stroke ratio
bore/stroke ratio
Cylinder Head flow/ cubic inch ratio
etc.
etc.
etc.

IIRC even Sonnys claims with bigger engines you get diminishing returns. I guess what it comes down to, is the 440 makes more low down torque, due to the long arm. If the 383 was .070 over, it should make more power at very high rpm. (4.320 vs. 4.320)
Food for thought....

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Yes there are lots of incidental physics but the big picture really doesn't change much: the 440 is 15% bigger and you can expect it to make roughly 15% more power than an equivalent 383....that's all there is to it.

The whole bore vs. stroke thing is largly an urban myth; there was a really good article I've saved somewhere (Hotrod?) that tested two Mark IV BBC's, both the same displacement but one had a much longer stroke and the other had a much bigger bore. The idea was to prove (or disprove) the theory that the long stroke motor would develop more low end torque and the short stroke motor would have more high RPM power......in the end there was only a couple hp difference between the two motors; a negligeable amount.

....yet still the urban myth persists in many circles. I WILL however concede that the 383 would have less friction losses, but in the real world it doesn't change the whole 15% thing a noticeable amount.

The bottom line is that 383's and 440's are very similar engines and using the same compression ratio, cam, heads, manifolds/headers, carbs, etc. will yield a difference in output VERY close to the difference in displacement. Of course if you use a carb that is too small (or any other missmatching of components), that will favor the smaller displacement motor.

Also, at the end of the day, even if I was wrong and the 383 is more efficient, it certainly wouldn't (and isn't) 15% more efficient and since the cost to rebuild the two motors is virtually identical, the answer to the original question remains....the 440 is cheaper to get to 500hp...no ifs, ands or buts about it.


Dave

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Another great opinion. Would with it:
Yes.. and NO!! Yes, the 440 may be cheaper to get to the 500hp level. NO, you cannot build the two
motors identical since they produce power at two different rpm ranges - 440 at the stronger low end to upper midrange, 383 at midrange to topend (cyl head/carb flow limit). Different design characteristics that can only be compared equally
by bore/stroke changes. Food for thought 57 cubes (440) vs an extended engine power peak rpm limit by nearly 1000 rpms (383).