So my stock auto transmission is dying in my '88 formula. To dodge the (rather unnecessary) work of setting it up as a manual, I'm looking toward a 4T60 swap. I'm running a 3.4 PR right now. When I get the car otherwise flawless, I plan on dropping in a turbo. Will the transmission be able to handle it? Would I be better off pulling out the engine and building a 3800sc, or should I keep the 3.4 since it's in? I've heard the 3.4 with a turbo is a tuning disaster but I'm willing to play with it as long as it's not an everlasting nightmare. What do you guys think, especially anybody with a 3.4 turbo setup?

The 4T60 is pretty stout after a rebuild with all the upgrades.
Should make a good drivetrain for your Fiero.

PM JCircs, he talked about selling a complete 3.4/4T60/Turbo dropout. He did it right. search for his threads.

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1986 Fiero GT Fastback 3.4Lpr with 4T60
1998 Jeep Grand Cherokee with "big boy" 5.9 motor
1983 Honda Goldwing 1100 Interstate

What sort of cash am I looking at dropping for a 4T60E revamp? I'll be putting the transmission in sometime this spring, but the turbo won't be until later. I'm not sure if I have the funds to rebuild now, before I drop it in. Is it so much work to get it running in the first place that I should just have it all done now?

Edit: wow, sorry, that was confusing. Is a transmission rebuild expensive enough that I should just worry about getting the 4T60 in for now, and break the bank on a rebuild later, or is it not worth the trouble of pulling it back out?

Edit: I'm being told that HD sprags, a 35/35 chain, and a 3.33 final drive ratio should more or less get it up to turbo capacity. Any upgrades missing from there?

[This message has been edited by BZAnathema (edited 02-06-2014).]

The 4T60E is a different trans from the 4T60. The Fiero ECM will not operate it.

Yeah,you will need a 440t4 or 4t60 nonE trans. The 4t60E and 4T65E/HD are electronically controlled by the engine computer.
The 440t4 and 4t60 nonE used a vacuum modulator and tv cable for shift inputs pretty sure.
Unfortunately there was only one 4t60nonE HD trans ever available,it came in 1989-1990 Mclaren grand prix turbo cars.
Fortunately,they use the TV cable and vac modulator differently somehow than others where one determines shift pressure and the other shift rpm so they are easily tuneable from what i've read.
Fortunately,I have one for sale in my garage sale thread in the for sale section!
Lol,sorry shameless bump for me but hoepefully info that helps you as well.

Thanks guys. The 4T60E was recommended in particular, as I was hoping the ECM could be programmed for it. That might be more work than I'm looking for. 4T60 it is, unless I snag a 4T60HD somewhere. Anyone rebuilt a 4T60 or have any idea what that rebuild might do to my wallet?

quote Originally posted by DefEddie: Unfortunately there was only one 4t60nonE HD trans ever available,it came in 1989-1990 Mclaren grand prix turbo cars. Fortunately,they use the TV cable and vac modulator differently somehow than others where one determines shift pressure and the other shift rpm so they are easily tuneable from what i've read. Fortunately,I have one for sale in my garage sale thread in the for sale section! Lol,sorry shameless bump for me but hoepefully info that helps you as well.

I wish this was available when I did my swap, that's the one I was looking for. I think you should make a separate ad for that item because I had trouble finding it even after your post in this thread.

JCircs thanks for the suggestion, i will do that right after I take some pics.
BZA good luck with your search/swap.