Hi....I am new to this site. I have a 1991 mustang GT and I am going to use a Ls1 from a 1999 trans am and a turbo 350 trans. I need to know if there are conversion motor mounts available or if I will need to fab some along with a tranny mount. And does anybody know what headers will work. I will need a wiring diagram to be able to wire up the PCM. I plan on buying a used PCM that has had a custom reprogram that omits the security system and is programed for a 6 speed car since I will be using a turbo 350 trans. I am also wondering about a drive shaft is there a conversion ujoint?...Any help would be appreciated. I am a GM tech and have been drag racing for many years. I am building this car on a budget just so I can beat the mustang boys with a chevy powered mustang.

 

Brp hotrods for mounts and headers, speartech harness and once the motor/trans is in measure for a driveshaft. Done. Try the conversion section i know multiple mustangs have been converted.

 

Search, click it.

 

You will find plenty of info on here about this swap as previous posters have said. Keep in mind that you can use the 4L60E speed sensor on the TH350 if you need a speed signal.

Jon
PSI

 

You can buy the AJE K-member setup for $400 with spring perches and mounts. That will allow the motor to drop right in.

You can either buy or make a tranny mount, again AJE.

For some reason there is not much info on the driveshafts being used. Usually it seems like everyone just buys one from one of the sponsors. Which will cost you right around $500.

 

What's up with using a 4l60e speed sensor on a th350? Haven't heard of that yet

 

Me either.

Will it work on a Th400?

 

The output shaft on the 4L60E has the same diameter as the TH350. You can replace the tailshaft housing and speedo gear with the reluctor. There are companies that sell kits to do this (about $100 with sensor, housing, gear), one in particular is not a sponsor here, so PM me for details. For a TH400 maybe a 4L80E gear will work, dont know because I havent tried it, or maybe the 4L60E gear can be honed out to fit.

Jon
PSI