I thought that a 250 cam would work in a 292. Are the cam journals different sizes? Clearance for rods?
Thanks,
Dave
the cams will fit but the lobe for fuel pump is different. not an issue with an electric pump, I ran a 292 cam in my 250.
A 292 cam can be used in the shorter stroke 250 without issue, but going the other direction will. Check out the 292 dyno test thread here to see what has to be done to successfully use a 250 cam in the longer stroke 292. The cam blanks between the two size engines are different in more ways than just the fuel pump lobe location.
IIRC?
Unlike the Gen-2 216, 235, 261 (which have the cam directly below the rocker arms and vertical pushrods), the Gen-3 194, 230, 250 have the cam placed outboard of the rockers which allows more clearance between the cam and the swing path of the connecting rods. In cross-section, the pushrods are not vertical, but tilt inward from the tappets to toward the rockers.
This was enough in the short stroke engines, but the 292 with it's much longer stroke doesn't have enough room for rod travel, so material is removed from the blanks to prevent contact.
Correct panic! A 250 cam will not work in a 292 without considerable modification to the cam barrel area. Simply using an electric fuel pump will not end the problems when swapping a 250 cam into a 292.
I'm right in the middle of this situation. I think it's easier and cheaper to replace the cam than modify the 250 cam.
Will Willis