[BlueOval]

My car doesn't sit too low, and it's got the 4cyl springs in the front. I changed out the rear with some Konis to make it even.

My car is a 90, and I bought a totaled 93 vert gt to make the swap. I ran into trouble with the main EFI harness from the ECU to the body harness. Pay close attention to the plugs in the drivers corner beside the master cylinder! There was a change, not sure exactly when..but I had to find a yard and trade for the correct one.

It's an easy swap, just time consuming.

If you remove the dash to access the grommet for the EFI (not always neccessary) replace the heater core now!!!!!!!!!!!!!!)

[3521]

Originally Posted by BlueOval My car doesn't sit too low, and it's got the 4cyl springs in the front. I changed out the rear with some Konis to make it even. My car is a 90, and I bought a totaled 93 vert gt to make the swap. I ran into trouble with the main EFI harness from the ECU to the body harness. Pay close attention to the plugs in the drivers corner beside the master cylinder! There was a change, not sure exactly when..but I had to find a yard and trade for the correct one. It's an easy swap, just time consuming. If you remove the dash to access the grommet for the EFI (not always neccessary) replace the heater core now!!!!!!!!!!!!!!)

Yah it's a brown 8 pin connector and the fuel pump relay is in the newer harness as well, I'm in that same boat trying to hunt one down so I don't have to do some wiring work, thats why I asked if he had the newer harness, I'd just trade him and from what and from what I can find it changed in 91 some relays under the seat some under the hood.

[Crob09]

+1 on the heater core idea. just do it while ur dash is out i did a 4 cyl to 5.0 swap in my 90 coupe. i carbed my motor so i kind of went the easy way but it wasnt too bad. just buy a used t-5 out of a junkyard cause i used my 4 cyl one and blew that AND the rear burning out lol. got any questions just ask

[Moses Man]

Originally Posted by BlueOval My car doesn't sit too low, and it's got the 4cyl springs in the front. I changed out the rear with some Konis to make it even. My car is a 90, and I bought a totaled 93 vert gt to make the swap. I ran into trouble with the main EFI harness from the ECU to the body harness. Pay close attention to the plugs in the drivers corner beside the master cylinder! There was a change, not sure exactly when..but I had to find a yard and trade for the correct one. It's an easy swap, just time consuming. If you remove the dash to access the grommet for the EFI (not always neccessary) replace the heater core now!!!!!!!!!!!!!!)

Right on, what is the five speed transmission they put in the four poppers anyway?

[LXpat93]

pretty much the same thing just weaker i thinks it the first gear that makes it weaker not sure though thats what this book about t5s said. it mentioned a 2.95 first gear making it able to handle the extra power id like to try it and see if it works. another question havnt swapped a motor yet i found a hell of a deal on a 5.0 to drop in my 4 banger. my dad told me not to do it cuz i got a good running little car and the 5.0 wont run like it should when i swap it but even if thats true i still wanna do it. having a 4cyl mustang and not swapping a v8 in is like having an itch but not scratching even though you know you can reach it. a parts list for the 5.0 swap will be a big help so i know what i gotta gather up thanks in advance.

[Squints]

some pretty good info in this link.
sorry, i don't have anything to add from personal experience or knowledge.


Changing a Fox Mustang from a Four Cylinder to a V-8 - 5.0 Mustang and Super Fords Magazine

[Notcho]

I did the 2.3 to 5.0 swap... I used my wrecked 89 5.0 LX car and put everything into the 87 2.3 notch. When I got the notch, there was no engine or transmission in it, but it was originally a 5 speed car.

I changed everything... I kept the efi, so i swapped all the wiring too. There are several seperate harnesses... the 5.0 engine itself has a harness on it, then that plugs into the computer harness with the large round black and white connectors, then that harness goes into the cab on the passenger side firewall and connects to the computer. The harness and the computer are different. They vary by year, as well.. The 88 and down cars didnt have mass air, and the 89 and up did. However, 90 and up had air bag, so 89 is a year in its own. For the engine wiring, remember to swap the MAP (manifold air pressure) sensor bolted to the firewall... the 4 cylinder one looks the same and it will plug in, but the car will not run properly with it.

The headlight harness actually is two piece. The main part, and then the front part. The front portion is different, because it also contains the alternator wires, which is longer for the 5.0 (alternator is in different place) The GT and 5.0 LX both had the same front harness, and they both have connections for the foglights.

I went ahead and used the dash wiring from the 89 5.0 LX, because I used the whole dash out of it. The 4 banger dash wasnt in too good shape, so I used the 5.0 dash. I just took it out in one piece. You can too, if you leave the plastic dash attached to the metal dash frame. It makes the swap a lot easier. I used the 5.0 steering column too. It had a tilt wheel and the 4 banger one didnt. From what I have read, all the wiring inside the dash is the same for the 4 cylinder and 5.0 cars. The only thing that is different is the gauge cluster. 89 and newer 5.0 cars had the 140mph speedo, and the tach is calibrated for the engine, either 4 cyl or 8 cyl and they wont work properly if you dont swap them.

I didn't swap any wiring besides that... I didnt mess with the fuel pump relay or any of the wiring. I used the gas tank out of the 5.0 car, and all the wires plugged in. The 4 cylinder and 5.0 gas tanks are the same, and the stock fuel pumps in the tank are even the same.

I did, however, change the front suspension, the k-member is the same for 2.3 and 5.0, (different motor mounts) A-arms are same, ball joints are same, but the spindles, rotors, calipers, sway bar, springs, and struts are bigger for the V8. I ripped all this off of the 5.0 car. The steering rack is the same. Apparently the power steering hoses are a little different for the 2.3 since it had a switch that would cut the AC off to save engine power for the power steering in emergencies. Since my 2.3 car didnt have the engine, it didnt have the hoses either. I just used the ones from the 5.0 car.

I also swapped ALL the brake lines as well as the master cylinder and booster from the 5.0 car. The rear brake line is different, since the 2.3 car only had the drivers side exhaust, they routed the brake lines on the passenger side. You DONT want to use this with the V8 dual exhaust.. it will heat the lines up and probably lock your brakes. Since I had the whole car at my disposal, I went ahead and swapped it.

The fuel lines are VERY different. The 4 cylinder ones come out of the tank, run along the passenger side then cross over the drive shaft onto the drivers side, then come up into the engine compartment on the drivers side. The V8 lines come out of the tank and run on the passenger side the whole way and come up on the passenger side in the engine compartment to fit onto the V8 fuel rails. The connections are also different on them, although the lines are the same size. The vent line that goes to the charcoal canister comes from the tank until just under the passenger door, where it stops. A plastic tube runs the rest of the way. The 4 cylinder car has a shorter plastic tube, but the metal vent line going to the tank is the same. I just swapped all these lines, they are held in by screws and rivets. I just used a grinder to remove the rivets, then I reattached the lines to the 2.3 car with rivets. The fuel tanks are the same for the 2.3 and 5.0 cars, as well as the fuel pump inside.

The vacuum lines are all engine specific, as well as the vacuum distributor, which bolts to the firewall by the brake booster. There is also a small cylindrical shaped vacuum resorvior on the passenger side under the fender. The 4 cylinder cars dont have that, so you need it too.

As far as the engine transmission driveshaft and rear end, I took it all from the 89 5.0 LX. The 4 cylinder and V8 5 speed transmissions are a little different, but mine didnt have an engine or transmission in it, so I don't know. The transmission crossmember is different. The one for the 4 cylinder has 1 hump for 1 exhaust pipe, and the V8 crossmember has 2 humps for 2 exhaust pipes. The 4 cylinder also only has one hanger just in front of the rear axle, and the V8 has 2, one on each side, and in the back by the bumper there are 2 more hangers for the exhaust. The radiators are different; the V8 had a bigger one. The 4 cylinder had an electric fan, and the V8 fan is bolted to the water pump. The fan shrouds are different.

the rear ends are different, the 4 cylinder has the 7.5 rear end and the V8 has the 8.8. I didn't try the 7.5 rear end because I went ahead and swapped them right away. The rear control arms appear to be the same, but I swapped them too. The 4 cylinder ones even have holes to mount a rear sway bar in them. The rear brake line connector is located in a different spot on the 8.8 and 7.5 rear ends. This is because the brake lines themselves are different on the car. I went ahead and swapped the springs and shocks too. I didn't compare them, but my V8 car had shorter springs (lowered) so I swapped them. The V8 rear end has a place to put the quad shocks, aka axle dampers. The 4 cylinder cars didnt have these, but they do have the holes in the frame to mount the plates. The e-brake cables are the same between both cars. The drive shafts are the same too, but the front yokes are a little different. If you are using the exhaust out of a V8 car, you should put the exhaust pipes in before you put the rear end in. It will be very hard if not impossible to do it later. Experience talking here..

The throttle cables are shorter for the 4 cylinder, and must be replaced. There are 2 cables.. one is for the pedal and the other cable runs to the cruse control module, which is under the drivers side fender. They look the same, but the 4 cylinder one has a shorter cable. The clutch cables are different, and the 4 cylinder cable will smoke your 5.0 clutch. I went ahead and swapped the clutch quadrant as well, because the 5.0 car had a nice aluminum bellcrank, and the 4 cylinder one had a cheap plastic one that looked ready to break.

One thing.. if you have a wrecked 5.0 car to take parts off of, the entire process is much, much easier. Out of all the junkyards I went to, I saw about 30 fox mustangs. Only 1 was a V8 car, and all of the 5.0 specific stuff had been taken out of it already.

I might be forgetting a few things, but I cant remember it all right now. My dad and I did the entire swap ourselves, and it took us 3 weeks to do it, working nearly all day, every day. It may seem like a lot of work, but it is a LOT MORE than you imagine... Nothing is really impossibly hard to do, but lots of things require 2 people to do.

If you have any questions.. just ask. I wouldn't have done this swap if others hadn't posted info about it, so I am paying it forward.

[Cool Bam]

I'm swapping my 2.3L > 351 Modified.

Good Trans and Rear end is a real good idea. Especially if you go crazy with upgrades later.

GL on your job thing also.