STL. Mark 11 Report post Posted June 13, 2015 I am restoring my 1969 Sports roof and I am thinking about going from my 302 to a 351. My question is can I still use my original c4 automatic? I am not sure if some used the FMX or not. Thanks! Quote Share this post Link to post Share on other sites
1969vert 55 Report post Posted June 13, 2015 302/351w/351c all the same tranny bolt pattern Quote Share this post Link to post Share on other sites
STL. Mark 11 Report post Posted June 13, 2015 Thanks 1969vert! This won't be a race car but I have the stock 302 with a 600 cfm carb, aluminum intake with full length headers so I am not sure if I want to switch. Quote Share this post Link to post Share on other sites
Rsanter 152 Report post Posted June 13, 2015 Yes you can Bob Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted June 13, 2015 I am assuming you are referring to a 351W. In stock form the FMX is stronger than the C4. That is why Ford used it with the 351W. Actually, up through the end of the 351W production in 1997 Ford had always installed larger stronger automatic or manual transmissions with the 351W than the 302 had. The C4 will fit like 1969vert mentioned. The FMX used a 164 tooth flexplate and a 28 oz. imbalance. I'm not certain how that interchanges. I'm sure somebody will chime in with all the details. If this is your first experience with a 351W, you'll be amazed how much more power the 351W has over a 302. In my opinion the 351W never got the recognition it should have for a performance motor. Quote Share this post Link to post Share on other sites
rwcstang 201 Report post Posted June 13, 2015 I have a built c4 in my 351w, same bolt pattern as the 302. one you go 351w, its a whole different animal lol Quote Share this post Link to post Share on other sites
69ISH 10 Report post Posted June 14, 2015 I am now running a 351W stroked to 408W with a C4 that was originally behind my stock 302W. I had the C4 built to handle 650 Hp and currently have approx 550 Hp (looking for more in the future). I stuck with the C4 as they can be built economically to be stronger than a FMX and are much lighter. I am not sure if you had a C10 in America but we have them here and they are stronger again than a C4 and stronger and lighter than a FMX. When and more likely if my C4 fails this is what will be going behind my 408W. Quote Share this post Link to post Share on other sites
1969vert 55 Report post Posted June 14, 2015 I am assuming you are referring to a 351W. In stock form the FMX is stronger than the C4. That is why Ford used it with the 351W. Actually, up through the end of the 351W production in 1997 Ford had always installed larger stronger automatic or manual transmissions with the 351W than the 302 had. The C4 will fit like 1969vert mentioned. The FMX used a 164 tooth flexplate and a 28 oz. imbalance. I'm not certain how that interchanges. I'm sure somebody will chime in with all the details. If this is your first experience with a 351W, you'll be amazed how much more power the 351W has over a 302. In my opinion the 351W never got the recognition it should have for a performance motor. you can use the 164 tooth flywheel with a truck C-4... 154 tooth normally a car transmission.. different bell ..... with the right stock parts..it will interchange..I run a 164 truck in my black car..stronger case.. and 154 was in my vert now its a toploader..He.He. Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted June 14, 2015 1969vert has good info on the truck version of the C4. I never thought of it. I think he meant 157 tooth instead of 154 tooth for the passenger car C4. Quote Share this post Link to post Share on other sites
Max Power 74 Report post Posted June 15, 2015 If this is your first experience with a 351W, you'll be amazed how much more power the 351W has over a 302. In my opinion the 351W never got the recognition it should have for a performance motor. That's because the competition made mostly stronger small blocks during the era. It's all in the heads Quote Share this post Link to post Share on other sites
TurboStangGT 7 Report post Posted June 15, 2015 Might want to give some thought to maybe using a AOD there's alot of performance parts for them or you can buy one already built that overdrive gear is nice. I've built two with no issues todate. just like everything else there's some years that are stronger than other years Quote Share this post Link to post Share on other sites
Grabber70Mach 107 Report post Posted June 16, 2015 Might want to give some thought to maybe using a AOD there's alot of performance parts for them or you can buy one already built that overdrive gear is nice. I've built two with no issues todate. just like everything else there's some years that are stronger than other years Any tips on setting up the TV cable on a carburated motor. Quote Share this post Link to post Share on other sites
takoarm 10 Report post Posted June 17, 2015 I went with a C6 behind my 351w stroked to a 427w. Wish I would have gone manual or a built c4. JBA headers didn't fit on mine with the shock tower delete and rod and custom rack and Pinion. Had to go with bbk headers. Quote Share this post Link to post Share on other sites
Sampa 0 Report post Posted July 10, 2015 Might want to give some thought to maybe using a AOD there's alot of performance parts for them or you can buy one already built that overdrive gear is nice. I've built two with no issues todate. just like everything else there's some years that are stronger than other years I'm planning on going with an AOD behind a mild 351W. A local trans shops says they can prep my '88 AOD for whatever I whatever I want. I do plan to upgrade the 351 eventually will likely go with something like the Holley throttle body F.I. set up. I'm open to any recommendations. I hope to make my '69 a daily driver. Quote Share this post Link to post Share on other sites