subframe question 3.8 to sbc swap

[Jon22188]

When swapping from a buick 3.8 to a sbc 350 using a turbo 350 what car would I need the subframe from?

 

[CHRIS.O]

You have a g body right? You don't swap anything other than the engine, trans, and mounts. There are other little things but no frame work needs to be done. You just pop the old engine out, buy sbc mounts, attach them to the frame and drop the other engine in. As far getting the engine in the car that is.

 

[Jon22188]

Yeah I have an 84 cutlass calais. Unfortunately it came with the sluggish 231. For the price Im getting the sbc 350 and turbo 350 trans I cant pass it up. I've never had a gbody before the cutlass so I've been doing a lot of research. From what I've read I would need to change out the subframe but with all the different options of transmissions I could use i'm not sure which one. I've mostly read people using a th350 but haven't read anyone giving advice using a turbo350.

 

[CHRIS.O]

Yea you don't change out a subframe. It is really simple to drop different engines in these cars. You will need sbc frame mounts which you could pick up at autozone. You would ask for sbc frame mounts for a monte carlo with a 305. You will probably need to change your cross member for your transmission. I don't know what trans you have now though so you may not have to. It is really that easy. All these g body cars use the same frame and all of them had options for other brand motors. So all you need is there.

 

[Jon22188]

Well the trans is equipt with overdrive. If that helps with knowing which trans it is.

 

[khan0165]

if your transmission is a th350, it is a 3spd auto, no overdrive

these cars have full frames... You might be thinking of the transmission crossmember, which is not a subframe, it is just a cross bar that holds the transmission up at the end

 

[Jon22188]

Yeah you're right haha im sorry i had a brain fart. But the transmission in it now has overdrive. Its not a th350. Its all stock as of right now.

 

[khan0165]

it might be a 200-4R then...
look at the transmission pan and see what you have

If you have a 200-4R, I would not get rid of it!

 

[Jon22188]

Yeah I really like the 4 speeds because I drive a lot of highway but how well would it hold up to a 350 if I got a plate adapter for it?

 

[khan0165]

plate? what plate?

it should handle a mild 350 no problem. You might need a stall to match your motor... but a stock or mild mannered 350, a stock stall converter should be okay.

the 200-4r has dual bolt pattern housing, so it will fit a Chevy and BOP (Buick, Olds, Pontiac) motor. And you can rebuild them with shift kits to handle ALOT more power.