How To Swap Buick V6 3.8 to SBC 350

[jcbannis]

i was thinking doing a sbc with th350 over the winter while im not driving my wagon. it had a 260 th200m now a 3.8 th350.. when installing the mounts will new holes need to be drilled for the mounts and from what i gathered if i use th350 chevy it will work on the oldsth350 crossmember? how much of the olds wiring will work on the sbc. just FYI ive never put in a chevy motor in anything. i had a 78-79 ford pick up and bronco addiction before my newfound Gwagon lots of 400m and 429's.

the holes should be pre drilled and a th350 old is all the same as a th350 chevy just different bellhousing pattern and the wiring should work also but the dist. maybe be different if your going with a hei

 

[1985cutlasssupreme]

would a THM200-4R fit on a regular 231 v6?

 

[maliburacinfreak]

would a THM200-4R fit on a regular 231 v6?

yes

 

[1985cutlasssupreme]

would a THM200-4R fit on a regular 231 v6?

yes

cool thanks for the help man.

 

[Member # 77]

V6 to LS1

 

[JJ7SKI]

ok quick question. i will be swapping a chevy 350/ th350 into my 86 cutlass. i currently have an olds 260 with th350 in it. my question is when the engine is mounted in the location shown in your pictures in the forward most holes of frame. will a short shaft th350 bolt right up to my stock cross member? and will my stock drive shaft work as well? where the olds 260 mounts to the frame its at the rear most mounting holes. this is about a 4 inch difference between the two locations. so im a little confused. help would be appreciated. thank you

 

[monsterenergy454]

i have a 1984 cutlass supreme and im putting in a sbc 327 from a 1969 impala but im sorta stuck on the whole mount thing i tryed something before but things didnt line up so ive beem researching and just found this which seems to be very helpful although im not quite clear on when you said to use "G-Body Specific Chevy V6/V8 Mounts". did that mean for instance could i go and get the mounts off of a cutlass that came with stock V8 and use them? and if so does that include both parts of the mount or could i use the part of the mount that bolts to the block of a chevy motor? any help would be great!!!

 

[neller840]

Great start to this thread!! I'm doing this exact swap.. I have a 1978 GMC caballero with a 231, and purchased a 78 monte carlo with a Targetmaster 350 sbc crate motor, and T350 transmission for a donor vehicle. I've pulled the motors out of both, and stopped at the motor mounts. I can't seem to find a way to access the bolts to the mounts unless I pull the front suspension apart.. At least separate the lower arm, and remove spring and shock to get access to the mounts. Am I missing a service hole, or is there a magic tool out there?? Thanks in advance!!

 

[Lowproelco]

I just did this swap on my elco went from a buick 3.8 to a sbc 355. I replaced all my front suspension so it was easier to asscess the motor mount holes... Its pretty much impossible to get them on or off without taking off the suspension.. i would just tkae it off and save yourself the trouble and fustration of trying to get those nuts started...

 

[neller840]

Thanks for the advice.. Ugh..... the only problem is I've already installed a Hotchkis TVS system on the front, and now am attemping the motor swap. Kicking myself for not just doing the motor right away.. The chicken came before the egg, and it's only breakfast... Thanks again!!