My friend installed a rear mount turbo t3/t4 on his 3.0L ranger and its amazing but I just was curious what size would I need for a single on a 5.7L .
I have an 87 GTA stock l98 and my goal is to reach the 350-400hp, run the car at 6 pounds boost nothing crazy and very basic.

 

youre probably better off talking to someone who has an sts kit and go by there specs but if i had to guess id say .81 a/r turbine T4 housing should do it with anything from a 60mm compressor wheel and up. i run a .96a/r on my 5.7L but i think with it being moiunted in the rear the .81 might help spool quicker, etc.
a master power MP70 (61.5mm) witha .81a/r should easily get you to your goal.
good luck

 

STS is great. Give them a call. They will talk to you about getting a kit perfectly made for your car. They will match a turbo to your mods done now and future mods, what do you want, quick spooling, more power, top end....they will find the right setup for you, just give them a call.

I dont want to see a response unless you called them and have feedback...