[ted200008]

i have a 66 bonneville with a 389. was wondering if i could put a small block chevy in it without changing the trans?? any suggestions are helpfull. thanks...

[455olds]

I am not sure what trans it has but the turbo 350-400,etc can be if you use an adapter as the bolt pattern is different. They are about $80 at summit last time I checked.

[ted200008]

i think its a powerglide but im not sure...

[FmrStrtracer]

Originally Posted by ted200008

i think its a powerglide but im not sure...

You will still need an adapter plate.

[g612gr@gmail.com]

Go to a transmission shop and find what they call a 350 B-O-P Case or Multi-Case. GM made a case that would fit not only Chevrolet, but Buick-Olds-Pontiac...should be plenty of them around.

[g612gr@gmail.com]

Sorry...don't think I gave you a good answer...if you have a B_O_P case you shouldn't have a problem. They didn't use power glides in Pontiacs...they used one similar called a ST300 and I don't remember if they used the Multi-Case...I don't think they did...so the other guy was right...you'll probably need an adapter plate. Probably less expensive in the long run...

[BOBCRMAN@aol.com]

Before you get into this. Check if the Pontiac starter bolts to the block or the belhousing. Pontiacs used belhousing mounts into the mid sixties.. An adapter won't do any good if the Chevy block mounted starter won't physically fit into the Pontiac belhousing. Been there.

[FmrStrtracer]

Just found this

Super Turbine 300s were the first GM automatics to incorporate multi-case bellhousings (ST300s were bolted behind BOP powerplants along with the Chevrolet inline six)

Look at the top of the trans case and see if it comes to a point in the center, or is it flat. If it comes to a point, it should bolt up to your Chevy engine.

Would really be better to upgrade to a T350. Extra gear really helps get the vehicle up and moving, while still retaining the 1:1 final drive.

[cobalt327]

The '66 should have the engine mounted starter holes present even if it used a trans mounted starter.

[WDCreech]

Originally Posted by BOBCRMAN@aol.com

Before you get into this. Check if the Pontiac starter bolts to the block or the belhousing. Pontiacs used belhousing mounts into the mid sixties.. An adapter won't do any good if the Chevy block mounted starter won't physically fit into the Pontiac belhousing. Been there.

Tha last full year of block mounted starters was 1963. There may have been a few in '64, but non NONE from '65 on.

[HRC]

Get a piece of 1/8 steel plate large enough to fit across the Pontiac tranny. Drill 3/8 holes in it as if you were going to bolt it to the Pontiac trans. Now, put it up against the back of Chevy block.. A couple of bolts should also match the Chevrolet block At least two of the bolt holes should match the Chevrolet block. Now, drill the other holes as if you were bolting it up to the Chevrolet. Okay, bolt up the 1/8 inch plate to the Chevrolet block using holes that DO NOT match the Pontiac tranny. You also need to make a half circle in the steel plate large enough to clear the torque converter. Bolt the torque converter onto the Chevrolet flywheel but put 1/8 inch washers between the flywheel and the torque converter to make up for moving the tranny back 1/8 inch. Now bolt up the Pontiac tranny to the adapter plate. Sounds harder than it is, but once you understand it you will see it's pretty simple. Been runnin' a Pontiac T-400 tranny behind a Chev. 350 for years with no problems. Should use Loctite on the converter bolts.

[WDCreech]

Originally Posted by WDCreech

Tha last full year of block mounted starters was 1963. There may have been a few in '64, but non NONE from '65 on.

I meant to say that the last full year of the bellhousing mounted starter was '63.

[cobalt327]

Originally Posted by WDCreech

I meant to say that the last full year of the bellhousing mounted starter was '63.

Does that include the full sized Pontiacs?

Thanks.

[WDCreech]

Originally Posted by cobalt327

Does that include the full sized Pontiacs?

Yes! In '64, I have read that the 421s and the GTO engines had block mounted starters. I didn't research this back in the day, but all indications are that it is true.

[cobalt327]

Originally Posted by WDCreech

Yes! In '64, I have read that the 421s and the GTO engines had block mounted starters. I didn't research this back in the day, but all indications are that it is true.

Okay, I appreciate it.