Quote Originally Posted by stovens
Tell me if this make sense. I'm using a computer program horse power simulator. Running equal components from heads, carb and cam the 429 ends up with about 50-60 hp, every time I run the figures, compared to the 460. I'm using Camquest 6 software from comp cams web site!
As to whether or not this "makes sense," my reply is that it makes sense only because it's a computer program. Of course it's wrong; you are playing with a computer program and not an engine build or even an engine combo of any kind.

Assuming all components being equal (including compression ratio) the 429 and 460 engines will make about the same power, the 429 generating that power at a slightly higher rpm than the 460.

Quote Originally Posted by stovens
The only thing I can think of is the smaller cylinder volume increases the compression and thereby the Horsepower. I just assumed the extra few cc of the 460, would equal extra horse power.
The fact that the 429 has a lower engine displacement will make its compression ratio lower than the 460, not higher.

You will be very, very restricted in performance piston choices if you build the 429. Which engine you ultimately build depends on application.

Paul