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I wasn't trying to bust anyone's chops with that reply. I think the engine "dyno" programs are generally misleading. The exception would be the most sophisticated and unsually expensive ones, and only when given very good and detailed data.

To generalize, cams will tend to move the torque peak rpm and change the shape of the torque coure, rather than add and subtract vast quantities of torque, unless something is really wrong. 40 lb ft just isn't realistically up for grabs here by going with a smaller cam.

Here's the peak torque results from a dyno test on a very basic small block Chevy, running all of the Comp XE cams, from the tiny XE250 to the huge XE294, run back to back with no other changes.

XE 250 475 at 3600
XE 256 472 at 3700
XE 262 476 at 4000
XE 268 479 at 41-4200
XE 274 477 at 4200
XE 284 477 at 4200
XE 294 480 at 4300

That is a pretty typical result.
-dulcich



The peak torque numbers might be close, but the torque curves are going to be quite different.
The small cam should have a fairly flat torque curve from 1,500 to peak torque than drop off fairly quickly. The large cam might be down as much as 100 ft/lbs @ 1,500 RPM compared to the small cam at the same RPM, and the torque curve will ramp up to peak torque, and fall off slower past peak torque.



You are precisely right with what you are saying.
-dulcich