I found this post on a Honda forum but he refers to the sbc 400. Are these safe assumptions when making cam decisions?
https://www.d-series.org/threads/cam...7/post-2178630
"There are quite a few variables which make the same cam have different power bands in different engines.
Most of my experience with the same cam in different engines is with Small Block Chevies.
On a 400 SBC I would expect.
For an idle of 600 rpm and maximum torque at about 2500 rpm and maximum power by 4500 rpm and nosed over by 5000 rpm you would need about 225 deg duration at 0.050 lift.
For an idle of 700 rpm and maximum torque at about 3000 rpm and maximum power by 5000 rpm and nosed over by 5500 rpm you would need about 235 deg duration at 0.050 lift.
For an idle of 750 rpm and maximum torque at about 3500 rpm and maximum power by 5500 rpm and nosed over by 6000 rpm you would need about 245 deg duration at 0.050 lift.
If you want it to rev to 8000 rpm you need about 285 deg.
For an idle of 700 rpm,
The trends are:-
The longer the rods, the higher the power band.
The longer the stroke the lower the power band.
The smaller the ports the lower the power band.
With the same heads and cam, a 400CI SBC will develop it's power about 700 to 800 rpm lower than a 350. If you use a long rod 400, it changes the peak power to 500 rpm less.
A 350 is 4" bore, 3.48" stroke with a 5.7" rod.
A std 400 is 4.125" bore, 3.75 stroke and 5.565" rods
Long rods are 6" long
If you use after market high port heads on a long rod 400 you can bring the rpm for maximum power back to the same as the 350 with the same cam.
Alternatively with the long rod 400 and the original heads, you need about an extra 25 or 30 deg of duration for 400 to make maximum power at the same speed as an otherwise identical 350."