hey guys the swap is completed on my 94 f150.. originally had a 302 with a 4r70w trans... swapped in a 96 351w and used same trans.... it cruises around pretty nice... but when giving full throttle and around 2500 3000 rpm it seems like it flattens out and flutters.. it never really get into any power.. not sure if its a fuel issue... it almost like the timing is not advancing not really sure like i said it cruises around fine... also is there any computer i could use for a 351 with the 4r70w trans... any help would be great

 

Unless you need to do a tune up, as in replace the fuel filter or have another mechanical part going bad such as the fuel pressure regulator, you shouldn't otherwise have a fuel issue because of the swap. My first guess/opinion is that the stock ECM may need a tune to accomodate the extra 50 cubes better. I have a '96 F150 with a 351W stroked to a 393 and when I had a custom tune programmed for the extra approx. 100 cubes, it made a huge difference in power, throttle response, and driveability. I'm not aware that Ford ever used the 4R70W with the 351W. I really don't know, but I had always thought that Ford always used the E4OD behind the 351W (when they switched to the electronic trans.), which is a totally different trans.

With your truck being a '94 which is OBDI, you could look into getting a custom chip made for the ECM. I personally have used a mustang A9L ECM in my old '86 F250 with my 393 before I swapped it into my '96 F150 and I thought it ran pretty well, of course, my engine was built for a work truck with low end emphasis and not high end horsepower. Sorry for the longish post, but there's my initial 2 cents.

 

did you use that computer with 4r70w trans?

 

No, I did not use the A9L ECM with the 4R70W trans.. I apologize for the confusion. I used the A9L ECM in a '86 F250 and also the engine wiring harness from a mustang, along with the supporting chassis wiring harness. The A9L ECM cannot control the 4R70W. It was never designed to handle an electronic automatic trans. In fact, the A9L ECM is for a mustang with a manual 5spd trans., if my memory serves me correctly.

I am currently using the stock '96 F150 ECM along with an SCT programmer for a custom tune to handle the extra cubic inches and firmer shifting from the trans..