351 probmels

[89Bronco58]

ok i have an 89 bronco that had an efi 302 and that blew up so i put an efi 351 in it...i changed the computer from another bronco that had a 351....is there more than 1 type of 351 computer??? cuz now it feels like its running rough and missin but it has new plugs and such...i put the 302 computer back in and it seemed to have more power and acceleration but it still lacks power....cuz the 302 moved the truck better than this 351 does...the motor has been sitting for a long time so i was thinking maybe it just needs to be cleaned out and ran for a bit???? ....anyone???

 

[BLADE262US]

First thing what tranny did the donor truck have ? What tranny do you have now ? Yes there is different computers there programmed with different timing curves per the transmission . I have one here for a 351 with an E4OD . Did you use the 302 engine harness on the 351 ? Have read that on some there are a couple injectors that need to be moved in the harness plug When I did mine I used a 351 harness so the only problem I had was from a 91 to an 89 there were a few important things in the harness that werent in the right places But I didnt have to mess with the injectors on that . /emoticons/[email protected] 2x" width="20" height="20" />

 

[mbtech2003]

what did u set the timing at?? :-B should be about 10 deg. btdc with the timing plugg undone. (under the distributer) also check and make sure the fuel injector seals arn't leaking >-

 

[hms79]

Besides all the computer stuff, you did mention the motor had sat for a while. I guess you rebuilt it? How many miles did it have? What tranny was it mounted to before? These are all things I would check after I did all the computer and tranny checking.