4cyl to 8cyl conversion questions.. convertible

sould not be, befor you start, get the subframes

Yes the wiring is diferent because you are dealing with a 4cyl and a 8 cyl. You need a computer and wiring harness for a 8 cyl.

maybe your seedo stuff, but it being a convertable or not makes no difference, if that's what your asking

1993SSP said:

I knew the comp would be diff, the main question is this, the wiring, from the computer forward is the only thing that needs changed right?? No need in changing the dash wiring?

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I just did this swap listen to me...I took a 92 GT Vert 5 speed, and put it all in a 91 Notch 4cyl auto

1. Change the motor, trans, computer and engine wire harness.

2. Change the headlight harness also. Reason being, the alternator plugs are on the passenger side on the engine on a 5.0L. The alternator plugs are on the driver side on the engine on a 2.3L.

3. You do not have to change the dash wiring. It is all the same, 4cyl, 8cyl, hardtop/conv/notch. All that goes to is the air bag plugs, headlight harness, and selenoid. All plugs are the same

4. Change the fuel lines. The fuel lines run on the driver side on a 4cyl. The fuel lines run on the passenger side on the 8cyl.

5. If one trans is a stick and one is an auto...you will need to change the transmission harness. No big deal...it runs along the drivers floor under the carpet, and plugs into a harness in the left kick panel area.
6. You will also need to change the clutch pedal box. The plugs that plug into the box, are all there on an auto car. Ford just put dummy plugs that loop a wire around.

7. Another thing too, the accelarator cable is run through a different hole in the firewall, but its not big deal. No drilling necessary, Ford just puts a rubber grommet in the other hole. Oh..accel cables and cruise cables are all different length too.

8. Just take EVERYTHING from the 5.0L and put it in the 4cyl car. I used all the the 4cyl suspension, I didn't change brakes, springs, spindles, struts, lowers, steering rack....nothing like that. I will though soon, just because the car handles like a 4ycl Mustang.

I would do this swap again any day. I did it in 3 days. 6-8 hours per day BY MYSELF. I had a hoist and a forklift. My only advice is to get a friend to help you. There were some frustrations I delt with because I had to man three things at once.

Yeah, thanks man. I tried to keep it as basic as possible, but include all of the B.S. stuff I ran into. Good luck, man mine is done, and it was worth every hour I put into it.

Since hes going to put it all in a convertible I think the brakes are the same as the 5.0 setup no? I know 50resto sells the brake booster/mc setup and the 4cyl convertibles and 5.0's have the same part number... only 4cyl coupe/hatch have the smaller booster setup (Different part number)? Maybe I'm wrong though?

Also if I remember correctly the brake lines are a bit different from the 4cyl to v8 when headed to the rear. I believe the 5.0 goes on the passenger side and the 4cyl goes down the drivers side. Don't forget to swap the fuel pump too. You will need the exhaust hangers for the drivers side too so don't forget those either. I'm doing this swap and I personally wouldn't do it again since I don't have a lift nor forklift its really difficult. It was a real pain but I must say I got time to redo everything while it was apart so in the end I have a nice setup with alot of new toys but overall the time it took from start to finish is enormous. If you wish to learn alot about your car and make it into what it will be then go ahead. You will learn alot for sure. Good luck with your choice.

I went into Autozone and Murrays, and they both showed me that the part numbers on the 4cyl and 8cyl fuel pumps are the same. I just left the 4cyl in there and my car runs fine.

You are right though about the 4cyl conv booster and v8 coupe boosters are the same.

The brake lines to the rear are the same, I didn't have to change them. You do need to change the lines from the booster to the top of the proprtioning valve. You also need to change the brake line that goes to the left front wheel. They are bent a little different, and I didn't want to mess with bending them, so I changed them.

SVT32VDOHC said:

The brake lines to the rear are the same, I didn't have to change them. You do need to change the lines from the booster to the top of the proprtioning valve. You also need to change the brake line that goes to the left front wheel. They are bent a little different, and I didn't want to mess with bending them, so I changed them.

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To the top of the proporting valve?? Explain this more... I didn't have to change any lines between the booster and the proporting valve. I did swap the booster / MC from the 5.0 and it mated perfectly to the proporting valve on the 4cyl car... I haven't driven my car yet but it doesn't seem to have any problems with that

I swapped the whole k-member from the 5.0 car to my 4cyl... Seemed easier that way to get the new spindle setup, brakes, steering rack, and having the motor, tranny, headers, and even the h pipe all hooked up. That made for an easy swap of everything. It was interesting getting that kmember all setup under the front radiator support but I got it in I'd truely recommend that style swap to save alot of disassembly + reassembly of stuff.

Well, when I put the V-8 booster in my notchback, I noticed that the V-8 booster was fatter than the 4cyl. What that did was it put the master cylinder farter forward. I had to use the V-8 lines from the master to the 4cyl prop valve. I tried using the 4 cyl lines, but they would reach the master without bending them. I didn't want to pinch anything, so I just swapped them.

The K-member swap with motor and trans is the best way. See I pulled my motor and trans out together through the top.

(I left all of my 4cyl suspension, but I am changing it later. The car is done, and I don't want to work on it anymore, I just want to finish the summer with how it is and ENJOY IT!!..I slaved on this car started May 26th, and Finished July 10th. I worked on it now and then stripping it to a shell, changing, the motor/trans,changing the color fixing the front end, doing body work and painting and reassebly in all of 12 days!!! I am burnt out.)

SVT32VDOHC said:

Well, when I put the V-8 booster in my notchback, I noticed that the V-8 booster was fatter than the 4cyl. What that did was it put the master cylinder farter forward. I had to use the V-8 lines from the master to the 4cyl prop valve. I tried using the 4 cyl lines, but they would reach the master without bending them. I didn't want to pinch anything, so I just swapped them.

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AHHHH YES I understand what your saying now... Yeah I used the v8 brake lines all around the car from the wrecked GT that I bought.

As for my car... its been off the road for almost a year and half now... but I went all out on my swap with a suspension and so on as you can probably see from my list of mods.

BTW you can fit the motor, tranny, and all that under the front of the car without removing the radiator support... but I HIGHLY wouldn't recommend it. I'm sure people would have loved to see how I got it under my radiator support, maybe even could have gotten a stickie if i took pictures ... It involved an engine lift (which btw didn't hold the engine... think about it), 2 jacks, some jack stands, some chain and 3 sets of hands... I left my kmember setup with the springs and struts attached and it also had wheels on it... I just got it high enough and rolled it underneath A very redneck way of doing it i'm sure (minus the fact that i'm not a redneck) but it worked and thats what counts.

I left my kmember setup with the springs and struts attached and it also had wheels on it... I just got it high enough and rolled it underneath A very redneck way of doing it i'm sure (minus the fact that i'm not a redneck) but it worked and thats what counts.[/QUOTE]

Not a very red neck way of doing it.....that is a very smart way of doing it. I would have done it that way too, but I was left doing this one myself. You should have seen the look on his face on Monday, when I turned the key and it fired up!!! Because he said that Friday, when he was locking up and I stayed and worked all weekend....