David, Here is my guess. Obviously the same camshaft would not be proper
for both strokes. I don't even think its the right one for either
stroke, but that just my opinion. Both motors would make about the same
power up to about 6000rpm. Then the short stroke motor would get better
by about 25-30 HP. Remember at 6500 rpm the piston in the long stroke
motor would be going about 4600 ft. per min. The short stroke piston
about 4080 ft. per min. That's my shot at the cupie doll prize.
Doug Odom in big ditch
Freiburger, David wrote:
>Let's assume you've got two big-block Chevys, both with 11.0:1, both with
>the same solid-roller cam (253/260 at 0.050 on a 111), and both with the
>same heads, intake, carb, oil pan, and headers. Both engines are 489ci.
>However, one uses a bore and stroke of 4.55x3.766, and the other is
>4.28x4.250. The rod-ratios are similar: the long-stroke is 1.53:1
>(6.535-inch rods), and the short-stroke is 1.63:1 (6.135-inch rods).
>
>What's the difference in the power curves and the required tuneup of these
>two engines and why?
>
>DF
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