3800 mods. How much boost?

I have a 1990 buick regal gs. It has a 3.1 liter in it. I hate that engine for it is really slow. As a summer project I'm trying to swap in a 3800 with a 4t60e transmission. I've done a lot of research on this subject and wanted to know one more thing. The engine i would be getting would be from a 94 buick regal or a pontiac bonnoville. That alone will not be all that fast, but i wanted to know how much boost can that engine handle? I can buy a supercharger for it that puts out 10 psi, but that's very little. I was thinking of getting a turbocharger that puts out about 16 to 20, but dont know if that engine can handle that. Thank you for any help you can provide.

10 pounds would be more than enough boost. Your poor tranny can't take much more than 240lbs-ft of torque, at least not with stock components. Good luck!

If you really want to boost, get the actual factory supercharged engine. Granted, only 7.5 psi of boost, but it will be much more reliable, and you could do other mods as well.

ive got similar problems... looking to swap out a 3.8 '91 regal gs engine and transmission.. into a 92 buick park av. ultra but keep the supercharger off the park av. Only thing im not sure if the tranny on the regal would be a 4t60e or the 440t4. ive heard of both on regals not sure though.

440t4

the 3.8L with the 4t60e tranny should handle 12 pounds boost stock.. the tranny will take at least 275lbs if its in good condition.

If you really want to boost, get the actual factory supercharged engine. Granted, only 7.5 psi of boost, but it will be much more reliable, and you could do other mods as well.


I would agree with this. A Motor that is already force inducted already has the lower compression, stronger pistons, ect. As far as how much boost. Your enemy is spark knock, keep the knock out of the motor and you should be fine, I run 24 LBS on pump gas and 27 lbs on 116 octane race gas. Alcohol injection as far as I am concerned is a must for anyone who wants to run High boost on a pump gas.