SC motor into a 83 mustang.

bye-bye-birdy

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Ok so my brother and me are going to help our cousin do the SC swap in his 83 mustang lx. The motor, trans, wiring, computer and whatever else we may need is coming out of my 90 XR7. The mustang is a 3.8 mustang so as far as motor mounts and drive shaft i believe we can use the stangs. Now what do we need to change as far as fuel system (since the mustang is tbi and the xr7 is efi) radiator, vacuum lines and things like that. The xr7 is a complete car minus the rear end which we wont be using anyways. Any help is appreciated thanks.
 
Hate to see a xr7 go....

I would ditch the 7.5 rear unless you dont intend on doing less than a 13 in the quarter. Also, on that topic, keep the diff from the cougar, you can still use the track lock. You could get a 8.8 housing from another mustang, and personally, i would use a track lock diff out of a f150. Cheapest way to go for a tough diff, has bigger cross pin and pinion gears. Use the ford motorsport carbon clutch rebuild kit and spring. I would also keep the drive shaft from the cougar, you can use the yokes. I would compare the tubes of both shafts, but you might need to go with custom tube.
Manual shift, auto?
You will have to do something about the intercooler. I would do a water to air. Probly the easiest way to go, and you can get the major parts to make it work on ebay for about 400.00.

This might suck, but just drop the engine in knowi g there will be problems and see what you find. Sure youll learn a lot doing that.

I would get tank and fuel lines from a mpfi 5.0. Not sure how the ends would work around to the fuel rail, but you might be suprised to find it works. Fuel system is really the same as the sc anyway. Dont forget the ircm. Pass front side of cougar. Controls fan, fuel pump and some other stuff.
 
May be easier to get a harness from a single port 3.8 sn95 mustang and get computer chipped...v6power.net may have more people there with experience swapping into a fox stang
 
Thanks guys and i am getting diagrams to do the wiring i am using a mustang tb bc i know the bracket is different on it and i am hoping the fuel lines and fuel pump in the stang is the same as the 5.0 so i dont have to change it... But i was told to redo the vac lines like they were in the xr7.. so once i wire the motor in do i have to change the wiring for the computer to make sure the pins r on the right connection.???? Will the car still run with out the knock senor and oil pan senor not connected?? I read somewhere that those wires wont be able to be spliced in bc the 84 stang dont have those.. and my bro wrote it was an 83 when its a 84.
 
Then you can more than likely just use that computer/harness and get get a chip with the proper programming to get it to run. Youll definitely need to change fuel pump however. The factory xr7 should fit but Id just get a new one
 
Then you can more than likely just use that computer/harness and get get a chip with the proper programming to get it to run. Youll definitely need to change fuel pump however. The factory xr7 should fit but Id just get a new one

Well.sence my cuzz is cheap I don't think he will chip it but I got an f3 chip laying around. But I was going to wire the motor in and plug the Xr7 computer vac lines fuel pump.. but I will talk to him and see Wat happens... Bc wiring the motor in... I may just chip it to make it easy....
 
Sounds like a pain, but i would strip the harness out of the dash and the bulkhead connectors to make it work. In the long run it would be easier than trying to make the other stuff work. Tbi stuff is really different. What i really meant was a 86 and up 5.0 fuel lines. Hold on to your aod, has good stuff in it. Better servo pistons and lower first and second gears. Just get it built. Shouldnt cost more than 2000.00 to build, unless you have bunch of broken hard parts.
 
Im thinking, you might as well start gutting all the engine wiring from the mustang because your going to use all xr7 wiring including computer. Figure out what wiring you will still need coming to the old computer of the stang, cut and label each one, splice into the xr7 wiring. Make sure you figure out wiring to the fuel pump and just connect that to your xr7 wiring. Some customizing you'll probably run into is connecting fuel lines. Driveshaft yolk may be different, so that may need changed at a minimum. I would take on that challenge given the opportunity.

I hope you will be using the XR7 transmission, you'll need all the transmission linkage hook-ups im sure. It will just be very time consuming im sure. At least you have a donor car to do it from. Good luck

chris
 
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Im thinking, you might as well start gutting all the engine wiring from the mustang because your going to use all xr7 wiring including computer. Figure out what wiring you will still need coming to the old computer of the stang, cut and label each one, splice into the xr7 wiring. Make sure you figure out wiring to the fuel pump and just connect that to your xr7 wiring. Some customizing you'll probably run into is connecting fuel lines. Driveshaft yolk may be different, so that may need changed at a minimum. I would take on that challenge given the opportunity.

I hope you will be using the XR7 transmission, you'll need all the transmission linkage hook-ups im sure. It will just be very time consuming im sure. At least you have a donor car to do it from. Good luck

chris

thanks Chris and everyone so this is my plan so tell me Wat u think.. drop in the Xr7 motor I am using all the wireing in the engine compartment of the Xr7 and transfering it over then tag and splice in.. hook up the computer hook up the vac lines like they were in the Xr7 run 5.0 tb and fuel lines and fuel pump. and we r useing the c4..
 
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