1983 Bonneville Wagon motor questions

[CoachFoust]

Hello All,

Yes, I'm new and I didn't search very well. I'll admit that, so if I post something that's been done or said before, please enlighten me as to its location. So here's what I have (or soon will have):

1983 Pontiac Bonneville, g-body wagon. It was originally a 305 V-8 car. My understanding is that the 305 in that year was a Chevy motor since Pontiac had discontinued the 301. Someone decided a few years ago to swap in a Chevy 454, get bored with the project and leave it to the next idiot (me). I just have this "thing" about having a big block in a car that's going to be my daily driver/cruiser. My intention is to swap in a Pontiac 400 and a BOP 200-4R, both of which I have sourced but yet to pay for. The 454 and its TH350 are mounted with drive shaft hooked up. I really want to put a Pontiac in a Pontiac (although it really came with a 305 Chevy), and I really want an OD trans. I think the trans swap would be fairly straightforward, but I'm unclear of the motor mounts needed for the 400, since the car was set up for a SBC and currently a BBC. I'm just needing a kick start in the right direction.

Thanks in advance, Coach.

 

[G-Body_Vet]

You're in the right place. There's a few of us running 400's & 455's in our cars. You'll need 301 mounts from a g-body and I believe '70 & up engines had the correct number of bosses to use those mounts. Most cars after '83 had the frame extension to use a 200-4R crossmember so you should be in good shape there unless something was different with wagons. I'm sure the rest of the Pontiac crowd will chime in shortly.

 

[CoachFoust]

So I could source the 301 motor mounts from my local Napa store if I said I was looking for "301 motor mounts from a 79 Grand Prix" for example?

 

[Longroof79]

Welcome aboard fellow wagon pusher. I think going with the Pontiac 400/ 200-4R combination is a great idea. I'm sure you could re-sell the 454 big block to someone.

Bonnewagon, one of esteemed members, could fill you in a bunch regarding Pontiac engine installation information. If I'm not mistake, he formerly had a 400 Pontiac in his Bonneville wagon, but went back to a 301. He would have to give you the details.

 

[Longroof79]

So I could source the 301 motor mounts from my local Napa store if I said I was looking for "301 motor mounts from a 79 Grand Prix" for example?

....or even an '83 Pontiac Bonneville. They're probably identical parts.

 

[CoachFoust]

Thanks! I'm really excited about this "little" project. This is my first wagon after several 2 & 4 door Malibus, El Caminos, a Grand Prix, as well as a Cutlass. Originally, I was looking for a Malibu wagon, but this Bonneville was too good to pass up. I really wanted the power windows, etc and that's a tough option to find in a Malibu. Things have just come together so far on this...I actually got burned last week trying to buy a Malibu wagon, but it worked out for the best. I think this is going to be a fun family cruiser that my 14 year old step daughter will never want to drive...she can have her Prius.

 

[Longroof79]

It should be a great family cruiser/ hauler. I think you'll really like it once it's running, and road worthy. You're absolutely right about Malibu's not usually being optioned like the Pontiac, Olds, Buick wagons...but that can be a crapshoot, depending on what equipment the original owner opted for.
Post some pics of your new acquisition...and of course, your progress. You've come to a great site, with many helpful people.

 

[G-Body_Vet]

....or even an '83 Pontiac Bonneville. They're probably identical parts.

Yes, you can buy the frame mounts pretty easily. It's the brackets specific to the 301 that you need. If you don't feel like hunting for them, I believe Butler Performance sells motor mount kits to help you accomplish a Poncho drive train.

 

[82GPLJ455]

I didnt see anything that would work on butlers site.you need the 301 gbody specific block and frame mounts.

block mounts can only be found used.be careful buying online,I bought a set that ended up being one side,firebird and the other was a big car.motor didnt look good sitting all crooked and sh*t.so for now im stuck with firebird block mounts wich have the motor sitting an inch too high till I can go get the right mounts I found.


The frame mounts can be bought brand new for 78-81 lemans,grand prix,bonneville with a 301.got mine from autozone for 5 bux each.

Exhaust manifolds are another issue.im not sure whats needed so somebody else can answer that.im using 78 firebird manifolds on mine.one of them(believe drivers side) dumps almost right on top of the lower control arm rear mount.exhaust shop had a hell of a time bending that pipe.

 

[motorheadmike]

I have a set of Pontiac frame mounts that were used in my wagon for about 5000 miles with a 455. They look pretty nice, shoot me a reasonable offer (think used SBC rubber mounts) and they are yours.