I have a 351w I took out of a 1990 Bronco with an E4OD and am going to put it in my brothers 1987 F150 4x4 that has a 302 and C6. Retaining the C6 in the 87 F150 and removing the worn out 302. My question is, does the E4OD flexplate that is on the 351W work with the C6, or does the C6 require a different one? If not, will the 302 C6 flex plate work on the 351w, or is there a balance difference between the engines that requires the 351w to use a different flexplate than the 302?

 

I'm doing a flex plate replacement right now on my 5.8.

Do not use a 302/5.0 flex plate on a 351/5.8 or vice-versa, they are not balanced the same, regardless of transmission type.

The flex plate on my 351's E4OD has a stamp on it "E4C6" (oddly enough, its stamped backwards) inside an oval. When I ordered a new one, the application states they can be used on an E4OD or C6 behind a 351/5.8.

 

+1 in this case you are OK to use the E4OD flexplate. For reference the 5.8 has a 28oz imbalance and the 5.0 a 50oz.

 

Thanks! That is exactly the information I needed! Will use the flexplate that was on the 351 with the E4OD.
This weekend I succeeded in finding an ECU from an 88 truck with a 351w and C6, so I have everything I need for the swap now.