I need some advice. I have a 1994 F-150 4x4 XLT Ext. Cab that had a 302. The engine didn't have the torque I wanted so I got a hold of a 351W. It came out of a 1994 van and has about 40,000 miles on it so I know it is a good engine. I know this because it is running in the truck right now.

I left the computer in the truck from the 302 and it does allow the 351 to run. It seems to run really well also (fires right over instead of having to crank forever). I haven't gotten much of a chance to test the engine/computer performance as the old engine is in the bed of the truck (it hasn't sold yet). I don't want to chance rolling it around and damaging something (like the truck).

My question is this: Will the computer for the EFI from the 302 work on the 351W? I have had a couple of people tell me both "yes" and "no". I called Ford today and they said it would work for a while but would likely burn up the existing computer after a while. Like I stated, it seems to run fine now, but I do not want to damage anything electrical and have a big bill later. I'd rather have the knowledge to know for a fact that it is or isn't gonna work.

Does anyone have reference materials or something concrete that they know for a fact that it WILL or WILL NOT work?!?!?!? I don't know where to go from here.

Thanks.

Forgot to add:
Truck has original automatic (with overdrive) transmission and 167,xxx miles. Tranny is going to be rebuilt in the next couple of weeks too. Nothing wrong, but just figured why not since going through all the trouble already. Slipped a little in the mountains when climbing to hunting spots.

 

just pull out the computer, and go to carb'd

then you'll hurt no electronics

 

It runs yes, but a 302 computer is not calibrated for the 351. For optimum performance get a 351 computer. I have not heard of the burning out problem before. I ran a 351 on a 302 computer for over a year.

 

INASHO, How hard was this swap? How well does your truck run with the setup you have? Is your truck mass air? I have the same truck and want to do the same swap. You can email me the details or post here if you want. Thanks in advance.

Bill

 

groundrat,

Believe it or not, it is as simple as pulling out the 302 and putting the 351 in. EVERYTHING bolted right up and plugged in WITHOUT modifications of any kind. If your A/C is in working order, leave it connected and tie off during the swap and bolt it up to the 351 when finished as it bolts right up to the same location.

 

groundrat,

Forgot to finish reply...the truck runs like new with no problems whatsoever (except the computer inquiry right now) and it is mass air. I do recommend talking to a salvage yard though to make sure the year motor that you get will have the same electronics on it as the year that you pull so you don't have modifications to do. Mine went from a '94 to a '94. The salvage yards have resources (programs and books) that they can look up what parts interchange with what (including engines I believe...not 100% sure though). Give it a shot!

 

inasho,

Is the fuel pump able to keep up?

I have done the same swap but the vehicle was dedicated to propane and now I want to swap it back to gas. Did you change anything on the fuel system?

Thanks,
Gavin Shafer

 

Thanks for the info. Did you use the full intake from the 351? Were there any parts from the 302 you had to reuse? Thanks for the help. Oh, was the 351w mass air?


Bill

 

My swap was done between different years so I needed to use the wire harness from the 302 and the accesory mounts for the powersteering and the air pump etc.

By the end of the weekend it will be running on gas for the first time since I have owned it.

I did change the computer on mine too.

Thanks,
Gavin

 

I'm doing the 302 to 351 in a 96 F-150. My two questions concerned the computer and intake system. Will the 302 intake adn fuel injection system work on the 351?

Thanks,

JIM

 

Jim Duck: the 302 intake will not work on the 351, physically different sizes.

inasho: If your engine has MAF I could be wrong about computer compatibility, mine was MAP, and the MAP engines definitely use different computers.

groundrat: inasho is right about bolt-in swap. I did it a few years ago.

 

Loudfords:

Thanks for the quick reply. Also meant to ask about exhaust manifods. Will they interchange from 302 to 351?

Thanks,

JIM

 

Jim Duck: you can bolt either exhaust manifolds on either engine, but there are slight differences in exit angles and diameters.

 

LOUDFORDS:

Thanks again for the reply. I have a 5.8 longblock and trying to determine if all the bolt ons (alternator, air cond compressor, water pump, power steering etc.) will work from my 5.0. Any other suggestions/recommendatiosn would be appreciated. I have been told that all the parts are the same, but you educated me on the intake.

Thanks.

JIM

 

Jim: The accessory brackets should bolt right up to the 351. The PS/AC bracket will use a different hole than 302 but both holes should be in the bracket. The alt/smog bracket bolts right up, you just have to rotate the smog pump and it's lower support rod slightly to bolt up. You're welcome.