Bonnewagon You Got MY 6?

Nope. Life got stupid and my spare time evaporated. I did acquire a billet steel front bearing cover to replace the cracked OEM cover from Passon. But that only fit the Chevy truck larger bell housing. So I had my machinist cut it down. I gave him a BOP bell housing, and the bearing cover, and he machined the cover to fit. It is all set ready to go now.

I have been struggling with the installation of a roll bar into my 1968 Firebird convertible project. The Firebird has a Pontiac 455 that I wanted to use the MY6 on. I considered swapping them both into the Bonnewagon. I have a Pontiac Turbo 301 that would replace the 455 in the Firebird. I miss the way the Firebird handled with the original light weight OHC-6. The 301 is about the same weight, but more power. When I had a Pontiac 400 V-8 in there the front end was super heavy. The roll bar has been eating up my time and causing me huge headaches.

But all this pales compared to the endless headaches life has been handing me. Family stuff, health issues, car problems, house projects, life has been ....interesting. That is why I spend time on here. It is a great escape. Oh, and fishing has been very good. Another time eater.

I had a small stash of MY6's that I played with years ago. I remember talking about them with Bonnewagon in a couple threads. I eventually sold them all when I went back to the stock M20 in my El Camino and decided to go TKO in my old pickup because I needed a more forward and centered shifter position. I really liked the MY6 in most regards, but they just don't shift as fast as a Muncie or Saginaw. I assume it's due to the rotaing mass of the heavier gearsets. If you just want to cruise and like the benefit of an overdrive, they're pretty cool.

stew86MCSS396 said:

Idk where to start...life presents your projects with many twists and turns. Once upon a time, I did acquire a MY6 trans and sbc large ibr bellhousing. It'll be easy to stick it behind a sbc/bbc or even a 4.3l v6 but a Pontiac 350 suddenly falls in my lap. Well, I used to have that bop bellhousing but got rid of it before acquiring the Pontiac engine. I do have what I believed to be a BOP bellhousing but after looking at it, realized it doesn't have a Pontiac starter pocket??? Some where along the venture, I've acquired T5s and T56s...so many decisions and you hafta ask why a MY6!!!

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Yup- life gets complicated. It is a wonder I can get stuff done at all. But I do still like the idea of a Pontiac 455 with the MY6. I read that transmission requires a good amount of engine power to be able to operate in overdrive. A 350/400/455 should be more than enough. Then around town you are actually operating a three speed manual trans. I once had a 1967 Firebird 400 HO parts car. I used to use the HD Borg Warner T-16 three speed trans whenever I busted up a four speed. It was indestructible. I was fine with the three speed for putzing around town. The overdrive would be icing on the cake for highway cruising.

Just to add insult to injury, after snooping around looking for that billet front bearing housing, I now see that someone must have made a run of them again. Maybe it was caused by me pestering all the vendors looking for that. I was on the phone with Passon and he quoted me a price of around $500 for the ones he had at the time. Then he rummaged around the shop and came up with a leftover from the first run. That only cost like $300 and I grabbed it. Now years later I see everyone selling it for $150. But it still needs to be cut down to fit the BOP bell housing. Unless you are a Chevy guy using the truck housing.

stew86MCSS396 said:

doesn't have a Pontiac starter pocket???

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Probably a Buick bell housing. Olds and Pontiac mount the starter on the driver side- Buick on the pass side. Old versions only had the pocket where needed, later versions had two pockets.

Pontiacs should have no problem pulling in OD. I ran mine behind a pretty basic 350 Chevy (Edelbrock Performer cam and intake with Qjet) and could get 22mpg. Later I swapped in a 400 SBC that was built for towing torque and routinely got 18-20mpg. 3.08 gears for both combos, lower gears would have been ideal. MY6 is very sturdy.

BTW, anyone with a basic lathe can cut down a stock MY6 "truck" front bearing retainer to standard "car" size in about 15 minutes. I did 2 of mine. Just took measurements off of a Muncie and duplicated. You'll need to use Allen head bolts for clearance when you're done.

DRIVEN said:

Pontiacs should have no problem pulling in OD. I ran mine behind a pretty basic 350 Chevy (Edelbrock Performer cam and intake with Qjet) and could get 22mpg. Later I swapped in a 400 SBC that was built for towing torque and routinely got 18-20mpg. 3.08 gears for both combos, lower gears would have been ideal. MY6 is very sturdy.

BTW, anyone with a basic lathe can cut down a stock MY6 "truck" front bearing retainer to standard "car" size in about 15 minutes. I did 2 of mine. Just took measurements off of a Muncie and duplicated. You'll need to use Allen head bolts for clearance when you're done.

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I'm glad you mentioned the gears. I have a 1979 TA disc rear with 3:08 gears. I also have a clean set of 3:23 gears. If I leave the ST-10 four speed in the Firebird, I will use the 3:08 gears. If the MY6, then the 3:23 gears was my plan.

I don't have a lathe, or know anyone who does. At the time the bearing cover was totally unobtainable. I trusted my machinist not to bugger it. Worse, the OEM was cast and that is probably why it was cracked. The OEM NOPAR cast versions were around but they are way too different to work. Now I see the NOPAR and Chevy versions available in billet steel. I guess interest has picked up.