would like to swap out my 267 in my 81 grand prix to ?????

[kcpets]

Hello, I got my grand prix free this last week and am looking into what i can do with the current setup and could use advise. I was thinking of getting a 350 but don't know if i will also need a diffrent transmission or not. I don't even know yet what transmission it has other then it's an auto. This is my first g body. If i could i'd stuff a 454 under the hood but i'd imagine that would take a lot of money and mods. thanks

 

[shotgun]

Do some searching here.

I am a Pontiac guy so guess what I would suggest.

Depending on your goal a nice mild P350 would work or if you want to go racing a 400/455 will bolt in with 301 mounts.

My GP had a 400 in it and will be swapping on a 600+ hp 440 (detroked 455).

Chevies are cheaper but I prefer the torque of a Pontiac on the street.

 

[kcpets]

will the 350 bolt up to the current transmission ? what transmission is in it to begin with ? thanks

 

[dougfather]

will the 350 bolt up to the current transmission ? what transmission is in it to begin with ? thanks

Which 350, Chevy, Buick, Olds, or Pontiac? The Buick, Old, and Pontiac engine use the same transmission-to-engine bolt pattern . The Chevy engine is different.

Assuming the 267 V8 you have now is a Chevy V8, a Chevy 350 will bolt up, but the real quetion is will it hold up? Which transmission do you have, a THM350 or a THM200? The 200 won't take the abuse like a 350 would. Now, if you have a 4-speed automatic (which was not offered until 1984 in the G-Body), that would be a THM200-4R, which has a dual bolt pattern.

 

[kcpets]

i'm not sure what transmission i have . Is there a way to tell with out having to crawl under the car ? here is my vin number. 2g2aj37j1b2543462. Not sure what 350 i'd like i was thinking chevy but if i could find a pontiac 350 or buick then i'd go that way. i would like a modest 300 horse or a tad more....lol

I'm sure my 267 is a pontiac motor

 

[kcpets]

i do know where there is a THM200-4R from an 86 for $150 would it be worth buying and swaping aswell ? and i also got an email from a guy with a malibu posi rearend for $125 complete drum to drum.

 

[dan2286]

Do you know what condition the trans is in?

 

[85 Cutlass Brougham]

If it's a 267 with a 3 speed trans ( IIRC, the only way they came) it's probably a Th200. If you are afraid to crawl under there and look, why would you want to do an engine swap? Crawl under there and look. If the pan says METRIC, it's a TH200. If not, it's probably a TH350C ( C= lockup converter). If the car is pre 1984, the TH200 4R requires welding to go in as you will need to add a mount to the driver's side of the frame to make it all work.

 

[84GP455]

I agree with Shotgun,,, keep it pure,,,keep it all Pontiac.
They are harder to find but well worth it. Most Pontiac V8's are interchangeable.

 

[kcpets]

i'm not affraid to crawl under just didn't want to right now as it has been raining and my parking spot has a small lake with god knows what swiming around in there lol as for welding not realy a problem as i am currently taking a welding caorse at university. if i can get my other ar out of my garage i'll jack it up and look