5.0 swap questions.
 

First time post, so hello and thank you in advance for any and all information. I know there will be one or two posters who tell me to do the research but I have been somewhat torn between an LS1 and a 5.0 swap but my mind was made up last night when I was donated the full drive train out of an 91 mustang 5.0. Unfortunately it is an automatic, but it did come with a posi rear end. My question is how difficult is it to work the automatic in, with later plans to swap it out for a 5 speed at a later date? Also, would the rear end from the mustang be usable?

I am on a slightly constricted budget but can do all of the labor myself or with help from a friend or two, but I just dont know if it is a viable setup or if the block is the only usable part of the entire setup. I know the driveshaft and half shafts will be worthless, but anything I can salvage will help considerably.

My Miata is a 94 in decent condition, and has been my daily driver for almost 13 years now. Its been a blast to drive up in the mountains but it lacks the oomph I crave. I grew up drag racing a 73 Nova, and just miss the V8 sound and torque. The donor of the mustang has a 96 Viper he races and I would like nothing more than to take him out with the engine he gave me someday. Anyways, Im just rambling at this point. Thank you for any input.

The Miata I will be tearing down has power steering and AC but I dont really care about keeping either. I know some fabrication will be in order to keep those but if its easier and less cost I will gladly give them up. I just want a clean build done right. It doesnt need any creature comforts. It already has crank windows, lol.

One of the problems with the automatic is it's a little more crowded for running the exhaust past the tranny. It's a lot wider than a T5. But it fits fine in the tunnel.

You can't (practically) use the rear from the Mustang. Many use the 8.8 or 7.5 from an 89-97 Tbird or Cougar, or the new Getrag found in many GM products.

I put an auto in mine, the original donor was a 93 Tbird, but I ended up using a 4R70W from a 96 Explorer. Fits in the same space. If you plan on a stick later, just leave the clutch pedal. Or take it out and save it for later. The Miata automatic shifter works with slight mods.

How are your fabrication skills? The front subframe has to be modified. A lot of conversions have been done with the Martin kit, see MRM331 posts, he has done 4 of them with that kit. Some feel that the kit has an unusual exhaust setup, but the alternative is more fabrication. V8 Roadsters will sell you a subframe without motor mounts, but they cater to the LS crowd, not Ford.

Welcome to the forum - ask lots of questions :)

Mike

You could always pick up a nice 4 cylinder Fox-body Mustang for cheap, & install your free drivetrain. No kit needed.

Thank you for all the information. I think I will just find a nice T5. There seem to be plenty floating around on craigslist for cheap. As far as the rear end I cant seem to find any of the cougar or t-bird rear ends. Ill just have to try the other options. The fabrication wont be too bad but I will most likely get the subframe from the kit if it can be ordered seperately. I have a lot of connections in the auto industry, and access to welders, painters, lifts, exhaust work, etc. so a lot of the work wont be too bad.

Getting a cheap mustang and swapping all of the drivetrain is an option but I just dont care for mustangs honestly, besides the exhaust sound. I would have prefered the LS1 route but its just not in the budget and free is a pretty good deciding factor. That and who cant have fun in a V8 miata? Ive had this car far too long and wanted to do something extreme with it for a while so its due time.

Thank you for the greetings. I will keep posted on the build when I get further along in getting parts. Have a good one guys.

For the differential, did you check the Pull-A-Part on Buford Hwy.? I recall seeing several T-birds & MarkVIII's. Not sure if the rear ends were still in them.

I havent gone up there yet. Thanks for reminding me. I havent been there since I built my Nova back in high school. Guess I have a plan for friday. :)