C1 (1960) Bellhousing

[Donald H.]

My 1960 had a '63 corvette aluminum T-10. I am hoping to find a correct project T-10 for the '60. I believe the correct aluminum bellhousing is casting #3764591. I have not removed the engine or transmission yet so I can see the current bellhousing casting number, but it is aluminum. Assuming what I have now is not cracked or anything, can I savely assume that it will work with the proper T-10 transmission? I'm trying to figure out if I need to starting looking for another bellhousing.

Thanks,

[Joe L.]

Re: C1 (1960) Bellhousing

My 1960 had a '63 corvette aluminum T-10. I am hoping to find a correct project T-10 for the '60. I believe the correct aluminum bellhousing is casting #3764591. I have not removed the engine or transmission yet so I can see the current bellhousing casting number, but it is aluminum. Assuming what I have now is not cracked or anything, can I savely assume that it will work with the proper T-10 transmission? I'm trying to figure out if I need to starting looking for another bellhousing.

Thanks,

Don------


There's an easy way to tell even with the engine and transmission still in the car. The 1960-only GM #3764591 bellhousing is a sand cast bellhousing with an open bottom which is covered with fabricated steel inspection cover. It is NOT configured like the "FLAT" inspection covers used for 1963 and later bellhousings.

However, if the transmission in the car now is a 1963 Muncie, it will NOT work with any pre-1963 bellhousing. In fact, it will only work with a 1963 bellhousing. So, if the car has a 1963 transmission, it must also have a 1963 bellhousing.

All of the 1963 and later bellhousings are die cast aluminum and are of "full round" configuration. If you have a full round bellhousing, which can be told at a glance, then you know you don't have the correct one.

There were only 2 sand cast aluminum bellhousings ever used on a Corvette. These are the 1960-only 3764591 and the 1961-62 3779553. These are functionally interchangeable. The only difference is the size of the clutch fork opening.

[Tom P.]

Re: C1 (1960) Bellhousing

Here is the difference in 60/61-62 bell housings that Joe is referring to regarding the size of the opening for the bearing fork.

This is a 591 housing which I have in my 56. As you can see, it has a smaller opening for the bearing fork.


This is the 61-62 553 housing which has the larger opening (oh ya, and for those of you who are ONLY familiar with Corvettes, this same bell housing was also carried over in 63 for the full size pass cars with a 409 ).

[Donald H.]

Re: C1 (1960) Bellhousing

Joe, my transmission is not a Muncie, it's an early '63 Borg Warner T-10. Can you tell from the pictures below if my bellhousing is correct for 1960.

Thanks

[Joe L.]

Re: C1 (1960) Bellhousing

Joe, my transmission is not a Muncie, it's an early '63 Borg Warner T-10. Can you tell from the pictures below if my bellhousing is correct for 1960.

Thanks

Don------

You have a C1 bellhousing but it looks to be a 55-59 cast iron piece, not the correct aluminum. Nevertheless, it should be 100% functional for your application.

Whether the transmission is a Muncie or a T-10, if it's a 1963 model year piece, it will use the small OD front bearing retainer. Such a transmission could be installed on a 1955-62 Corvette bellhousing but it's not only NCRS-incorrect, it's also FUNCTIONALLY incorrect and I would NEVER recommend such an installation.

The front bearing retainer FLANGE outside diameter is designed to fit with very little clearance into the orifice in the bellhousing. This helps support and stabilize the engine and transmission assembly.

In an installation like yours, there is a great clearance between the bearing retainer flange OD and the orifice in the bellhousing which obviates the design support feature. I don't recommend this, at all. This is a "bubba" sort of thing.

I suppose it's possible that someone converted the 63 Muncie to the larger flange OD bearing retainer. I've not seen that done but I suppose it's possible (although another "bubba" sort of thing). However, most likely the transmission was installed without concern, or even knowledge, of its functional incompatibility with a C1 bellhousing.

[Tom P.]

Re: C1 (1960) Bellhousing

Don------

You have a C1 bellhousing but it looks to be a 55-59 cast iron piece, not the correct aluminum. Nevertheless, it should be 100% functional for your application.

Whether the transmission is a Muncie or a T-10, if it's a 1963 model year piece, it will use the small OD front bearing retainer. Such a transmission could be installed on a 1955-62 Corvette bellhousing but it's not only NCRS-incorrect, it's also FUNCTIONALLY incorrect and I would NEVER recommend such an installation.

The front bearing retainer FLANGE outside diameter is designed to fit with very little clearance into the orifice in the bellhousing. This helps support and stabilize the engine and transmission assembly.

In an installation like yours, there is a great clearance between the bearing retainer flange OD and the orifice in the bellhousing which obviates the design support feature. I don't recommend this, at all. This is a "bubba" sort of thing.

I suppose it's possible that someone converted the 63 Muncie to the larger flange OD bearing retainer. I've not seen that done but I suppose it's possible (although another "bubba" sort of thing). However, most likely the transmission was installed without concern, or even knowledge, of its functional incompatibility with a C1 bellhousing.

Ummmmmmmmmmmmmmmmmmmmm, sort of.
The 63 (ONLY) full size cars with a 409/4sp, as I mentioned above, used the 61-62 style alum bell housing (553)----------------------WHICH OF COURSE, had the larger hole for the front bearing retainer. Soooooooooooooooooo, to make the 63 4spds compatable with the hole in a 553 housing, the same style front bearing retainer that was used on 62-earlier 3spds was used on the 63 4sp trannys. Thus, this would NOT be a bubba fix-----------------IT WOULD BE A GENUINE FACTORY CONFIGURATION for the 4spds used in 63 409 4sp full size cars. Consequently, he COULD have a 63 4sp that was originally behind a 409, OR, someone could just as easily install a 3sp front bearing retainer on a 63 Vette 4sp tranny and the result would be exactly as it was on the 63 4spds used with 409 cars.
(I don't have the part number for the 3sp front bearing retainer to fit the 63 4spds, but I can dig it out if anyone desires)

[Joe L.]

Re: C1 (1960) Bellhousing

Ummmmmmmmmmmmmmmmmmmmm, sort of.
The 63 (ONLY) full size cars with a 409/4sp, as I mentioned above, used the 61-62 style alum bell housing (553)----------------------WHICH OF COURSE, had the larger hole for the front bearing retainer. Soooooooooooooooooo, to make the 63 4spds compatable with the hole in a 553 housing, the same style front bearing retainer that was used on 62-earlier 3spds was used on the 63 4sp trannys. Thus, this would NOT be a bubba fix-----------------IT WOULD BE A GENUINE FACTORY CONFIGURATION for the 4spds used in 63 409 4sp full size cars. Consequently, he COULD have a 63 4sp that was originally behind a 409, OR, someone could just as easily install a 3sp front bearing retainer on a 63 Vette 4sp tranny and the result would be exactly as it was on the 63 4spds used with 409 cars.
(I don't have the part number for the 3sp front bearing retainer to fit the 63 4spds, but I can dig it out if anyone desires)

Tom-----

Well, I really doubt this transmission originally resided in a 1963 409 full size Chevrolet but if it did, it would be compatible with the C1 bellhousing.

I did not realize that the C1 3 speed transmission bearing retainer and the 63 409 bearing retainer were the same, but having now checked, I see that they are. It was GM #3741458 and it was discontinued without supercession in July, 1986.

As you say, if the above retainer was installed on a 1963 T-10, that transmission would be fully compatible with any C1 bellhousing. However, I would strongly suspect that was not done in this case. It would be easy to tell, though when the transmission is out of the car. The 3741458 retainer should show that cast-in number and the OD of the flange will be 4-11/16".

[Tom P.]

Re: C1 (1960) Bellhousing

No, no, no, I'm not trying to say that is what he has, I'm only saying that it how it COULD have been, or, could be changed so that it would fit the 553 housing (or as you mentioned, fit any other housing).
That same front bearing retainer (for a 3sp) also fits the 63 Muncies that had the small 63 style front bearing retainer. Of course, this was all 63 unique configuration stuff. In 64, GM obviously realized their error and went back to the 62-earlier configuration.
I've run across a lot of variations and strange things after 40+yrs of building/repairing torque tube 3spds and 55-later 3spds, ODs and 4spds.

[Donald H.]

Re: C1 (1960) Bellhousing

The bellhousing is aluminum and not cast iron. The pictures I posted earlier aren't the best. But I just went out and looked again and even tested with a magnet.

The transmission is a T10D-1 serial number 3110290. I was told from earlier posting that it was from an early '63 vette before GM switched to Muncie.

[Tom P.]

Re: C1 (1960) Bellhousing

If you will compare your housing (SPECIFICALLY the fork holes) very carefully to the 3764591 housing that is in my 56, I think you will see that it is very probably the 1960 ONLY 3764591 housing. ALLLLLLLLLLLLLL 60-later Vettes got an alum bell housing (60-62 had the open bottom style). But in the full size pass cars, only the hi-perf 348 and 409 cars got the alum housings, all other manual tranny cars had iron housings. And by 63, EVERYTHING (except trucks) had alum housings.

[Joe L.]

Re: C1 (1960) Bellhousing

The bellhousing is aluminum and not cast iron. The pictures I posted earlier aren't the best. But I just went out and looked again and even tested with a magnet.

The transmission is a T10D-1 serial number 3110290. I was told from earlier posting that it was from an early '63 vette before GM switched to Muncie.

Don------


OK, it just looked like cast iron to me, especially in the photo on the right. In fact, when I looked at the photo on the left, I thought it was cast aluminum but when I looked at the photo on the right I thought I was wrong and it was cast iron.

This is good because it means that you have the correct, 1960-only bellhousing (as identified by the clutch fork opening configuration). These bellhousings are probably the most difficult of all Corvette bellhousings to find so you're lucky you don't need to go looking and PAYING for one.