67 350 to 427 engine swap

[My427C10]

Been getting conflicting information regarding small and big motor mounts and frame towers. I have a 67 short wide bed with a 350 in it and I'm swapping for 1969 427. Bought used 1971 big frame towers, but 2 holes at frame are about a little over a 1/4 inch difference, so not sure they will work. I was also told that small towers will work as long as I move them forward from where they were with 350. Never thought this would be so difficult. Please help.

 

[61Apache]

I've heard that '72 big block towers work best, not sure what the difference is, but the part numbers between '71 and '72 are different. From my personal experience, small block towers will have the engine sitting to low and you will not have clearance for the exhaust manifolds. Headers will yield the same problem, no clearance.
Use the big block towers you have, just elongate the existing frame hole, if necessary for the proper bolt locations. Make sure to use "grade 8" hardened bolts and nuts on the install. HTH.

 

[My427C10]

Thanks for your information. I didn't think of elongating the holes in the frame. Good suggestion. Glenn