Re: My 86 442: update 8-15-10
The 5A 307 heads would be an excellent direct bolt on, if rebuilt too factory spec's with just surfacing them no more then .010, everything from the roller cam engine will fit with no problems or modifications. But as stated earlier the full benefit would be using the intake and exhaust manifolds that go with the 5A heads or going with aftermarket intake and headers.
The 5A 307 heads would be an excellent direct bolt on, if rebuilt too factory spec's with just surfacing them no more then .010, everything from the roller cam engine will fit with no problems or modifications. But as stated earlier the full benefit would be using the intake and exhaust manifolds that go with the 5A heads or going with aftermarket intake and headers.