if you're doing this by collecting indiv parts, forget it unless you plan on going carb'd.
I've helped my friend with this converting over an 89 4 banger notch auto to a v8 5 speed.
I assume you want to convert to make it look "factory" and do this the "right" way without cutting corners.
Really, the only way you should do this is to have a wrecked parts car on hand, and you want the same year, or darned close, as their are slight wiring changes across years that can throw you for a loop.
My buddy had a totaled 89 vert, and he put everything onto the 89 notch.
now, before I go into detail, I must say this is a VERY easy job.........for the mechanically inclined. It is extremly laborious and time consuming, but everything is straight forward.
To do this the proper way:
yank EVERYTHING from the 4 cyl chassis. This is assuming it's an auto and you want a v8 5 speed:
-yank the engine, trans, ecu, ecu harness AND engine bay wiring harness. Dash wiring harness and body wiring harness stays. yank the pedal assembly, center console, ALL fuel lines back to the tank, and the rear end. yank the front rotors AND spindles off.
Notches started life as a v8, and were adapted at the factory for a 4 banger. that's the good news. the only thing you'll need to do for that k member to hold the v8 is to remove the 4 cylinder engine mount brackets. 2 bolts, and they're off, drop in your 5.0 and trans all in one pop. The v8 car has the trans x member a little further back, so use the v8 trans x member. Brackets are already present in car.
Great, you've got your engine/trans bolted in. Before this, I should have mentioned to swap in the quick ratio steering rack from the v8 car. Do this while the engine is out. this is simple. Swap in all the fuel lines from the v8 car from the engine back to the tank. swap in the v8 engine bay wiring harness, and ecu and ecu harness. Swap in the v8 spindles and rotors, then swap in your 8.8 rear. I forget, but you may have to swap in the v8 brake lines.
swap in the clutch pedal assembly, clutch cable, and any other odds and ends.
this is why you need a v8 parts car, you're essentially trading EVERY mechanical part.
forgot to mention, swap in the v8 springs too.
If you want to cut corners, you can skip most of the wiring by going carb'd, leave the 4 banger brakes on, leave the 7.5 in, and leave the 4 banger springs on. You'll have quite a sloppy ride, but you can shortcut this.
!....one good thing about the 4cyl mustangs is more than likely the chassis are in good shape meaning the torque boxes are usually not torn up like the V8 cars usually are...and yes everything needs to be changed out!...as an example you will tell yourself something like "i will just keep the small 4cyl brakes on there for now" yeah right!....i dont mean to discourage you but just wanted to let you know my experience!.....i will try to answer some of your questions so just ask away!
