are they the same

 

The block is taller on 351 so the heads are further apart. They are not the same. I ran into this when i put a 351 in my 88 150 were a 302 used to be.

clipper

 

Um...I'm confused...

It should be a direct bolt on swap. I put a 351 based 393 in my truck using all of the 302 accessories. It just needs a longer belt.

Yes, the heads are further apart, but they still bolt in the same places and will fit with a longer 351 belt.

This is on a serpentine system I'm talking about.

 

i to was able to retain my accesories , at least the ps pump and ac bracket. I installed a 95 5.8 so it used a different Alt/smog setup compared to my 88 302.

clipper, maybe the 351w block you were using was a 70's block or you had a 351m

 

I too had a belt alignment problem with my 302-351 swap. For some reason the accessories pulleys did not linup with the crank pulley when I mounted all the 302 brackets. I managed to fix the problem by changing the accessory brackets.. there were slight differences in the 2 sets I had. The misalignment was bad enough to destroy a brand new belt in 15 minutes.

 

I did have to use a pulley spacer, but I also used a performance products balancer instead of a stock one.