4 cyl-V8 swap help needed.

[Mikes88GT]

Ok guys I'm picking up a mustang roller that is a former 4 cyl/5spd car and need to know what is needed to do a 4 cyl to V8 swap. I want to keep it a 5spd and fuel injected.

How hard is it to go from the 4cyl wire harnes and computer to the V8 wire harness and computer?

Is there any difference between the 4cyl K member and V8??

Any help would be great.

I also need all this stuff so I will be posting a wanted add:p

[BIGG]

k-members are the same, you will need to swap over fuel lines 5.0 on passenger side and rear brake lines if your running a 8.8 rear end or you can adapt them over, splice in, what year is your car?

[BIGG]

should swap front rotors and spindels ,5.0 are bigger,5.0 also have the smaller brake booster

[Mikes88GT]

Car is a 1991. So the fuel lines need to be moved to the passager side along with the break lines??

[BIGG]

the problem with thw brake lines is when / if you swap in a 8.8 rear the rear end flex line is on the drivers side,they both run down the passenger side,the 5.0 crossover just in front of the torkbox for the lower diff. arm, you may be able to make a brake line from the 2.3 flex line

[BIGG]

the fuel line on the 2.3 runs down the drivers side and connects to the engine on that side. the 5.0 runs down the pass side and connects to the engine on that side, pass,

[BIGG]

i dont think you can just swap the fuel lines to the passenger side, i have a donner 91 5.0 lx notch im using most of the parts out of inc rear brake lines and fuel lines from that to engine also the brake booster and spindles, rotors & rear end

[Mikes88GT]

Thanks for your help!:-D

Will the 5.0 harness and computer plug in in place of the 2.3's harness and computer or will I have to rewire?

[BIGG]

what year is your harness

[Mikes88GT]

I don't have a harness or computer yet

[BIGG]

i was looking in my factory wiring diagrams for the 91 mustang, i think you will need a harness form the 92-93 5.0 mustang beacuse the 91 2.3 has the fuel pump relay in the ircm under the hood and the 91 5.0 has the fuel pump relay under the drivers seat

[RdRunnr]

i was looking in my factory wiring diagrams for the 91 mustang, i think you will need a harness form the 92-93 5.0 mustang beacuse the 91 2.3 has the fuel pump relay in the ircm under the hood and the 91 5.0 has the fuel pump relay under the drivers seat

For his conversion, he MUST use 90-91 computer and headlight harnesses for the swap to work. The early 92 is also the same, but I would stick to 90-91 to be safe. 92.5 - 93 are unique to those years and 87-89 are also unique. Been there, done that, with my conversion.

[BIGG]

you can use a 88 -93 5.0 maf computer,but i think you will need the 92-93 5.0 harness

[RdRunnr]

you can use a 88 -93 5.0 maf computer,but i think you will need the 92-93 5.0 harness


See my message above. I KNOW what harnesses he will need based on EXPERIENCE, not from studying diagrams. The 88-89 Mass air harness is unique to itself because they do not have an airbag, 90-92.5 are unique because they have an airbag and the fuel pump relay under the seat, and the 92.5-93 are unique because they have the airbag and fuel pump relay under the hood. The safest route to take is if the car is a 91, to just find harnesses from a 91 so you will know they will be plug and play without any re-wiring. Also a 88 computer is speed density unless is came from a California car. The computer needs to be 89+ for mass air. You will also want to find a headlight harness from the same year car. Otherwise you will need to rewire the alternator as the wiring won't reach the other side of the car. Again it's best to try to find this harness from a 91, as the plugs vary on this harness too.

[Mikes88GT]

Thanks for your help guys! I def want plug and play!

So I need to look for 90-92.5 mass air harness and a 92 headlight harness. For the computer 89 and up. And here's the million dollar question....... Anyone have the above mentioned stuff sitting around??:-D

[BIGG]

i have the harness for a 91 5.0 its different from a 90, the 90s have 2 connectors by the self test connector 1 black and 1 grey, the 91-93 have 1 brownish colored connector by the self test connector but the 92-93 have the fuel pump relay under the hood near the maf sensor, my 88 is a calif with maf, i know the 88-89 fed cars dont have maf, i dont think my 91 harness with the brownish connector will work on a 91-93 2.3l can to swap it out? i dont lots of research and hands on still learning the difference but i think i have it figured out, i own a 87 gt t5, 88 gt t5 vert, 89 gt t5, 91 lx notch 5.0 t5,93 lx hatch , larry

[Mach1Dan]

Try to find a 5.0 harness that is the same year as your car and it should swap right in. I did it a few months back on my 93 Lx and everything snaped together no problem. Both harness's were 93's. I don't think it matters if it is an auto or a 5-speed harness. Computers don't seam to matter as long as they are mass air .( For 89 up cars of coarse.) Everything I read said that there are differances in harness's from year to year but some years may be closer than others. I was not willing to bet on that, so I looked on E-bay till I found the same year.(I had a 88 harness and it was way different.) Good luck with your swap. Dan