Hi, Everyone.................
I am looking for some information on, or someone that's had some knowledge on swapping out a 302 EFI engine to a 351w EFI.
We own a 1986 full size Bronco, we are in the process of ording a new 351w series II engine from Autozone.
My understanding is that the 302 EFI manifold will not bolt up to a 351w engine. So I was going to purchase a Edlebrock EFI Performer 5.8L intake manifold. Will be also purchasing headers,water pump, computer, harmonic balancer, distributor and starter. However I'm not sure if any of the outer parts off of my 302 would work, or if I'm going to have to purchase all new hardware. I am going to purchase new injectors, but was wondering about the wiring harness and other attachments. I am also wondering if any of the pully brackets would work from my 302 as well?
Any information on this or recommendations would greatly be appreciated.

 

Alot of the accessory brakets will not work. Anything that bolts to the front of the head will not work because the 351W puts the heads out wider than the 302. Also, stock y-pipe on exhaust will require modification. Believe it or not, the 302 starter would have worked. Go to the lobby and do a search on 302 efi/351efi swap. That way it will search all the forums. I remember somebody did do the electrical thing and it was a good discussion.

 

Thank You! for the responses, I do appreciate this information. Keep them coming.
Any information on this matter will help.
I will keep an update to this conversion as we go along.
Again Thanks.

 

Well I found out today why it's not a popular 302 to 351w EFI swap out.
I was told Ford did not entertain the 351w with EFI until 1988. Only the 302 had EFI. So I guess it means that our 1986 full size Bronco is going to be a problem. I haven't found out what the wiring differences are, but I'm sure theres a big difference. I was thinking of finding a wrecked 88' or 89' Ford with a 351w EFI and all wiring and computer, and install it in our Bronco, but not sure if it's worth the effort.
So I guess I'm going to just change out the 302 with a new 302 motor.
If any suggestion, they would be appreciated.

 

Johnfl on the 80-96 list successfully put a 351W EFI in his 86 and I put one in my 87 so it can be done easier than you may think.

1979 F150 Custom: nothing under the hood at all (again)
1987 F150 XLT Lariat: 88 351W EFI
84 351W: soon to have 91 heads, Crane PowerMax cam, double roller timing chain, Edelbrock Performer intake & Holley carb and be put back in 79 F150
86 & 87 Bronco II: next winter's beater

 

I believe you can get an adapter from Ford for about $50 that will allow you to use all of your front mounted accessories. I researched that several years ago and PAW and a few other Ford conversion folks had the bracket as well. The starter should also be the same, but the flexplate and harmonic balancer will be balanced differently than the 302. Or.....you can get a complete set of brackets, pulleys, and water pump from Zoops for around $1200. It sounds like a lot, but it is all billet alluminum and top quality and everything fits correctly. It looks great, is light, top quality, and strong.

Good luck,

'82 F150 2WD w/351W (orig 300 I6)
Slik

 

Im just finishing up a 302 to 351 swap in my 89 f-150, all the stock motor mounts work, same bell housing, same flywheel.Actaully the wireing and fuel system wasnt even that bad. I went from a computer with the 302 to duraspark 2. and from fuel injection, to a 4bbl. works realy good.

 

You're buying the engine from Autozone, as in autoparts store? How does that work? Are they expensive? Thanks.

Daywalker
92' F-250HD 351 4x4 xlt 4.10 ZF 5speed supercab longbed

 

An update and to say Thanks! For all the support and suggestions that you are sending, we do appreciate it.

An update to what we hope to be a success. We went to Las Vegas on July 20th to look for a 351w EFI engine. We went to Abbie’s Pick-a-part. They were very helpful in accommodating us. They had a 1991 351w EFI engine in a pickup, but I was too concerned about the year differences from 86 to 91. So we did a little more checking, to our surprise came across a 1986 F-150 4x4 pickup. It had a 351 EFI. After looking at the engine, it looked identical to our 302 EFI, (i.e. Wiring, valve controls, front of engine, and brackets), except the intake manifold says 5.8L. We were led to believe that Ford did not make a 351 EFI in 1986. So we were not sure if this is a conversion setup, or if it’s the real deal. Anyway we made a deal to purchase the complete engine, wiring harness, computer, and the control modules. We purchase it all for $1000.00. Don’t know if it was a good deal, but hope so. After getting home did some more research, which seems to be so limited for 1986 Ford’s and 351 engines. I am thinking more and more that the engine is from a different year, or they used a 302 wiring harness and computer conversion?
We still want to purchase the engine II series from Auto Zone, It will cost about another $1800.00 but think it’s a smart move. These engine are supposed to be balanced. We will use all of the outside parts from this engine we got from Abbie’s to make the completion (i.e. Intake, wiring and computer). Will be buying, new injectors, headers, high performance clutch, and any other amenities.
I know it looks like were are spending more money than needed, “no were not made of money”, however I wanted to build a good solid engine to last a long time. So we thought this would be a good way to go, and be able to do an engine upgrade. We were just looking for the upper half (i.e. EFI intake manifold, but new we would need other parts as well, because of the 302 to 351 differences. I know some of you would say just rebuild the used engine, however in our location, we do not have a machine shop or one that could be recommended, that’s why for the Auto Zone engine.
We are interested in any further comments that you may have, or suggestion and we will keep updates if you are interested. Again thanks for the support.

 

hopefully u got my personal message. i got everything to do a 351W minus the block and the front accessories. I got the heads, intake, roller cam, oil pan/pickup tube, exhaust manifolds, throttle body, distributor, EGR and all sensors, clutch, etc. (i think i forgot the clutch on the e-mail). (3 boxes full of stuff). All stuff is brand new never used, I bought a longblock from Ford and pulled all of the truck stuff off, because i was dropping it in my mustang. I placed an ad yesterday, but it sent me an e-mail saying it would have to be read by someone before it is posted. let me know if you are interested.