Inliners International Forums General Discussion Drive Train Can I use an early M20 Muncie behind a 261?

I have an early M20 (casting no. 3831704) that I think that I want to put behind my 1954 chevy 261 six. However, the diameter of the bearing retainer is about 4.182 inches and the bore in each of the three bellhousings that I have is about 4.680 inches. Is another bearing retainer available or is an adapter ring available, or could one be turned by a normal machine shop?

I also have an early Corvette V-8 3-speed that I could use. Are rebuild or shifter kits available for this transmission?

I nkow that I should probably use a more modern transmission, but I have been dragging these around for over forty years, and I want to stay in the early sixties or earlier, except for real safety items.

Hoyt, II# 922

If there is enough area out side the bolt pattern Im sure a machine shop should be able to turn them for you.

While you could have one made, I'm sure it wouldn't be cheap. There is a factory one available, just search for it.

Dear Mr. Hoyt;

Buffalo Ent. can help you. There # is: (360) 652-7684.

I use a 55-62 bell housing for mine, but that has It's limitations etc.

Good luck.

Hoyt,
Are you sure about those numbers?
Seems like there backwards. The later trannies and bellhousings should be the 4.68, the '54 and earlier car bellhousings have the 4.18 hole in them.??

What vehicle are you trying to do this in?

Dear Mr. Hoyt;

The newer transmissions have the larger retainer as Brian says.

The 55-62 Bell Housing will work on all Chevrolet passenger cars except 49-54 and some trucks, as I recall. This is where you will need the adapter mentioned.

Call Buffalo for the particulars/prices etc.

Good luck.

John, Gearhead, et al.,

I have three chevy six bellhousings (of unknown origin; one must be from a truck as it has a foot starter and another has a R/H side throwout arm) with the "wide" transmission flange that mates with the Muncie four-speed or the Corvette three-speed. Each bellhousing has the 4.68" bore, but the Muncie does have the 4.18" OD bearing retainer. Paul of 5Speed.com tells me that the 1963 Muncie did come with the small bearing retainer, and that a larger diameter version is available, but he did not have one. He referred me to a Brian at SK Speed. Tomorrow I will call both Brian and Buffalo for more info.

Back in the early sixties, I had the Corvette three-speed behind my 261 in a '53 Chevy with an open driveshaft Spicer rear end. In 1965 I bought the Muncie transmission to put in my '62 Impala 327 when I thought that its four speed went out; however, the problem was just a broken shift linkage, so I have been just dragging the Muncie ( and the 261, the Corvette three-soeed, and lots of other stuff) around for the past 40+ years. I am now trying to do something with it all. I never noticed that the Muncie bearing retainer OD was smaller than the bore in the bellhousings until recently when I installed the 261 in a '32 Ford highboy. I want to use one of these transmissions as I am trying to pretend that it is still 1964 (except for brakes and real safety equipment).

Hoyt, II # 922

Mr. H;

The 'right side' housing (release fork) came from a truck (60-62) with an hydraulic clutch.

This might be good for a 32 highboy.

The early model (pre 55) Chevy 6 bell housings have a smaller retainer hole and different bolt pattern & N/G for a later (55 & up) transmission W/O the adapter etc.

Good luck.

As for the input collar, you could also try Zumbrota Bearing and Gear 1-507-732-7994 M-F 8-5 central time ask for Craig. They also sell on Ebay under zbag648. They actually have a Muncie collar on Ebay right now for $18, assuming it uses the same input bearing as your tranny...

Considering the project you are building, and the fact that you are not trying to use a 37-54 car or 37-47 truck bellhousing, then the adapter from Buffalo is irrelevant.

Once you have changed over to the larger input collar, any 48-62 truck or 55-62 car 6cyl bellhousing can be used, but some are better than others depending on how you are going to use it. The differences are in the motor mounts, foot starter, and fork direction.

55-62 car has no provision for a foot starter, and I'm not certain what it uses for motor mounts. My guess is that the 55-57 has mounts, but that the 58-62 doesn't???

48-53 truck has foot starter and "square" corners for a saddle type mount.

54-57 has foot starter and angled corner mounts.

58-59 no more foot starter, still angled mounts.

60-62 angled mounts and a hydraulic slave cylinder activated clutch fork on the pass. side.

If anyone has more to add (or correct) feel free...

The 60-62 one that you have could be the one to use, especially if you are using swing pedals. Hook up a slave to the pedal, and just run a line down to the other one on the bellhousing, and you're all set. No mechanical linkage to screw with. Of course, the others can be converted to hyraulic if you prefer. A hydraulic throwout bearing setup could also be used. It all depends on what you want. Mechanical linkage is also doable, but may be more work, again it depends on what you are using for pedals, etc...

Gearhead, et al.,

Thanks much for the bellhousing descriptions. The one that I have with the foot starter has square corners with two tapped mounting holes on the vertical sides; the other two have the angled mounts. I am using the transmission pad as the aft mounts with the '54 side mounts on the engine block for the front mounts. If I did it right, a photo of the installation is in the link. Right now, I am planning on using the foot starter and a hydraulic throwout bearing. I'm using under-floorboard pedals.

Craig from Zumbrota tells me that the $18 retainer that he has on ebay wil not fit the transmission bearing of the '63 M20. However, he just sent an email saying that he has a retainer that will fit, so I will call him tomorrow.

Thanks much for all of your help. Great1

Hoyt, II #922 261 installation

No need to make it complicated, just go to a wrecking yard and buy the front bearing retainer, throwout yoke that's the right size they are interchangeable. I have done that several times.