efi 5.0 wiring question

I just picked up a 91 mercury grand marquis with a super low

I would definitely use the EFI. There are several companies that make wiring harnesses just for this swap, such as Painless, and there are others. Do a search for "5.0 EFI swap mustang", and you'll find plenty of info.

John

66 2+2 (soon to be EFI)

Interesting that you are doing this, I am doing the exact same swap. You could put this setup in your car, but it is not the same as a Mustang

5.0. The firing order is different, among other things. There AREN'T a lot of companies making wiring for this swap. There are several companies making wiring for Mustang EFI into 60's Mustang, but the donor car is a 89-93 Mustang v-8, not a Mercury or other 5.0. So, if you go through with this, you can pay ($1000 at least) for a custom harness or make a harness yourself. I am going to convert the 1990 Mercury 5.0 I have to carburetored until I can get a donor 89-93 Mustang.

Take that for what it is worth,

Gary in NC

"Claud Spinks" wrthe Mote in message news: snipped-for-privacy@yahoo.com...

You're right, there are differences. I believe only the Mark 7 with the HO package used the same sequential roller 5.0 that the Mustang used. The other corporate 5.0s do have differences. Again, the OP should do a search, he'll find plenty. Windsorfox.com is a good start.

John

66 2+2

'84/'85 HO motors used in the LTD LX and Marquis LTS were rollers but CFI not EFI induction. StuK

The HO 5L shares the 351w firing order. The standard 5.0l has the normal 302 firing order, FYI of course :-)

///Mike

1993 BMW 525i of all the old cars

I appreciate the replies to my question, Again, I'm by far not a ford expert. What I logically can't understand is that if I were to use this non HO 5.0 that runs great in the big merc, using the complete engine, sensors, computer (virtually everything), why wouldn't the engine run as well after the swap? I did a search on the 5.0 EFI swap and when reading one of the articles it mentioned about the non ho's run poorly when used in a conversion. I could be wrong...but? I just have to figure out what wires are for what to wire the computer. Thanks again, LeRoy

The Mercury and the Mustang have differant goals, so they use the same basic engine, but with differant tuning. Not a big deal unless you're building a high performance car. If you're building a fun daily driver, the Mercury is probably a better choice. The computer, ignition, etc, is all differant from a Mustang, so don't try and swap parts.

Since you have the whole car, you have everything you need. Simply grab the wiring harness, trans, etc, from the mercury, and bolt it in to the Mustang. Put the computer behind the dash, just like you would with a Mustang swap. Take a look at how it's done with Mustang parts, and follow the same basic directions. Piece of pie; easy as cake.

I think it will run great. As long as you're not building a balls-out high performance car, the Merc is an excellent donor choice. Just don't try and swap in some Mustang performance parts, it all will be well.