302 SEFI to a 351 carb conversion

[87_crown_vic]

i have found a person with a 351W that is carbed. i was thinking of swapping that in to replace the engine in Deuce. what would i have to do to get it to work? i was wondering if the oil pan would transfer over? i know that i am gonna have to gut a lot of things from under the hood also. what would i need to do to get this to work? any help is apreciated.

Jim

[DuceAnAHalf]

you will need a 351W oil Pan, auto Zone sells one for around $80, also any Mustang 351W swap pan will work if you can find one cheap on eBay. I made up a thread about doing this swap, it is somewhere in the archives.

[interceptor1985]

Ditto! my buddy has a 351 HO from an ol bronco that I can have for the tudor and I definitly am planning on doing the swap!

[87_crown_vic]

i am trying to figure out what i will have to gut to make it work. i know i need to pull the fuel pump from the tank, i am gonna have to figure out how to wire the alternator, i need to figure out how i am gonna run the fuel lines. i know that the oil pressure sending unit and water temp will be done into a regular gauge instead of the dummy lights. i am gonna want bucket seats and remove the rear. it will be only for 2 passengers. it will be a stripped down version of a 2 door. it will weigh less, and have lots of go. i wanna get 4 piston calipers, drilled and slotted rotors, and black nascar type rims. it will be a true toy. all that i would need done after that is to swap it for a 5-speed.

[gadget73]

Unplug the ECM and just pull all the wiring attatched to it. It will all unplug. The EFI harness is self-contained. Don't cut anything, someone else might need the harness, or it may be useful for one of your other cars. For the relays, just unscrew the bracket and leave them plugged in. Same with the smog controls over on the fender. Some of that stuff changed year to year, so if anyone else uses that harness, having the relays still attatched might be useful.

[interceptor1985]

Mine is CFI so what would be the difference there? I was raised with the EFI Vicky's so CFI is all new to me..

[gadget73]

Same idea converting CFI to a carb. Same mods to the fuel system, and the wiring comes out pretty much the same way. No big plugs at the firewall to connect the engine, but the harness will still come out in one piece if you're careful.

[1987cp]

+1

Rip out all the fuel injection wiring, hook up the ignition system of your choice, and that's pretty much it. For CFI, do some research and verify the output pressure of the in-tank electric pump; if it's under 10 psi, it might be easiest to regulate it to 6 psi for the carburetor. Otherwise, I think my mechanical fuel pumps are pretty handy. Cheap, provide the correct fuel pressure without regulation if you select the right pump, and no wiring to worry about. Someone remind me to dig up my pictures of my modified sending unit/fuel pickup assembly.

[DuceAnAHalf]

You can but regulators that will regulate EFI pumps down to a carbs <7psi. You will need a bypass style for best results. My pump puts out something like 20 psi and I'm running a non bypass regulator.

[nfldfordltd]

Your alternator system doesn't need to be changed, modified or altered> I had an 89 Grand Marquis with factory 351 W 2bbl. and that car had the standard 65 amp alternator with IAR. Just use all the bracketry and pulleys and stuff from the old 302 and it should all work fine.

[1987cp]

It's actually not hard to make an all-new alternator harness to eliminate the toasty-wires problem some guys have reported. The plugs can probably still be had new from your favorite discount parts store (I got mine at a Murray's in '03).

[87lxcoupe]

I don't know if this info will help but, I'm looking into going over to a 351 also. In my case, I'd really like to keep the A/C. The factory shop manual shows a different a/c bracket for the 351 in a Vic. They have an exploded view of the 302 setup as well as an exploded view of the 351 setup. Of course, if you're not keeping the a/c you have no problem. If you do want to keep the air, I don't know where you'd find the rear a/c bracket. Maybe a Bronco or F-series? I don't know. I'll try to download the pictures from the manual if you need them.

[1987cp]

I'm remembering the rear A/C bracket as bolting to the passenger-side exhaust manifold on both 302 and 351 models, which would be why I'm not running one at present on the car with the compressor still in place (took me a minute to remember that ... headers = no place to bolt stock rear A/C bracket). I will admit that since I have no belt on the A/C for the time being, I don't know how it will actually perform without the rear bracket installed. The front bracket from my tired '79 351 looked different than the one I took off my '87 302, but it did bolt right up to the 302 I put in its place.

I do remember that on the '87 motor there's one head bolt with a stud on top, which isn't currently used for anything, so I'd imagine that could provide a mounting spot for a custom or modified rear A/C bracket if swapped to a handy location once the stock exhaust manifolds are removed - if you happen to be reusing a set of stock head bolts with that feature, which is a pretty big "if".

[NATEHAWK]

Take a look at my thread on my build it shows all the steps and a detail process..

http://www.grandmarq.net/vb/showthread.php?t=9018

[gadget73]

Ac bracket doesn't bolt to the exhaust manifold. It bolts to the head, and the front plate with the tensioner goes from the AC bracket to the water pump. 302 and 351 AC brackets are different. You'd need one from a 351 police car to retain the AC. They're not impossible to find, just need to do some looking. No idea if truck brackets work, but I doubt it.