Bellhousing Depth

[Joe C.]

Does any one know the depth of a "403" bellhousing?

[Joe L.]

Re: Bellhousing Depth

Does any one know the depth of a "403" bellhousing?

Joe-------


6.29" from the block mating surface to the transmission mounting surface. This dimension is the same for the "383", "403", "444" and "621" bellhousings.

[Hugh G.]

Re: Bellhousing Depth

Joe-------


6.29" from the block mating surface to the transmission mounting surface. This dimension is the same for the "383", "403", "444" and "621" bellhousings.

Would the 6.29" measurement be true for a "421" bellhousing??

[Joe L.]

Re: Bellhousing Depth

Would the 6.29" measurement be true for a "421" bellhousing??

Hugh------


Yes.

[Hugh G.]

Re: Bellhousing Depth

Thanks for the infor. I'm using a 383 on my 63 and hoping for not unforeseen problems.

[Joe L.]

Re: Bellhousing Depth

Thanks for the infor. I'm using a 383 on my 63 and hoping for not unforeseen problems.

Hugh------


There will be no problem as long as you use the 64+ front bearing retainer. However, the 1963 transmission cases were not designed for the use of this retainer.

[Joe C.]

Re: Bellhousing Depth

Joe-------


6.29" from the block mating surface to the transmission mounting surface. This dimension is the same for the "383", "403", "444" and "621" bellhousings.

Thanks Joe.

[Tom P.]

Re: Bellhousing Depth

Hugh------


There will be no problem as long as you use the 64+ front bearing retainer. However, the 1963 transmission cases were not designed for the use of this retainer.

Well, sorta.
In 1963 ONLY, the front bearing retainer on 4spds was smaller than 55-62 and 64-later transmissions---------------------EXCEPT, EXCEPT, EXCEPT on 409 cars!!!! The 1963 ONLY 409 cars with a 4sp used the SAME front bearing retainer as was used on 55-62 3sp transmissions. SOOOOOOOOOOOOOOOO, all that is needed to be done to fit a 63 only transmission into a 64-later bell housing is to round up a 55-62 3sp front bearing retainer and install it on a 63 4sp. TOOOOOOOOOOOO EASY!

Oh ya, also, beginning with 1955 cars (pass car, Corvette, doesn't matter), all bell housings (cast iron or alum) are the SAME depth. Think about it------------from the front face of the transmission case to the pilot on the end of the input shaft, the dimension on ALLLLLLLLLLLLLLLL Chevy manual transmissions (3sp, 4sp, doesn't matter) is the same dimension. Thus, the dimension from the front to the rear of all bell housings has to be the same----------------and that includes truck bell housings which were used for 12in clutches.

[Hugh G.]

Re: Bellhousing Depth

Well, sorta.
In 1963 ONLY, the front bearing retainer on 4spds was smaller than 55-62 and 64-later transmissions---------------------EXCEPT, EXCEPT, EXCEPT on 409 cars!!!! The 1963 ONLY 409 cars with a 4sp used the SAME front bearing retainer as was used on 55-62 3sp transmissions. SOOOOOOOOOOOOOOOO, all that is needed to be done to fit a 63 only transmission into a 64-later bell housing is to round up a 55-62 3sp front bearing retainer and install it on a 63 4sp. TOOOOOOOOOOOO EASY!

Oh ya, also, beginning with 1955 cars (pass car, Corvette, doesn't matter), all bell housings (cast iron or alum) are the SAME depth. Think about it------------from the front face of the transmission case to the pilot on the end of the input shaft, the dimension on ALLLLLLLLLLLLLLLL Chevy manual transmissions (3sp, 4sp, doesn't matter) is the same dimension. Thus, the dimension from the front to the rear of all bell housings has to be the same----------------and that includes truck bell housings which were used for 12in clutches.

Thanks guys. Sadly my 63 has a t10-C that has the larger front bearing retainer plus the wrong bellhousing (1958) and a 163 (higher tooth count) flywheel (1959). I did not know I had the incorrect trannie till I tried to fit a "421" on the it. Luckily I did fit check on the bench prior to attempting to install it. As I stated I just bought a "383" and it fits fine and matches up with the correct flywheel. I'm now looking for a 1962 July-Aug t10-D trannie to mate with my "421".

[Joe L.]

Re: Bellhousing Depth

Thanks guys. Sadly my 63 has a t10-C that has the larger front bearing retainer plus the wrong bellhousing (1958) and a 163 (higher tooth count) flywheel (1959). I did not know I had the incorrect trannie till I tried to fit a "421" on the it. Luckily I did fit check on the bench prior to attempting to install it. As I stated I just bought a "383" and it fits fine and matches up with the correct flywheel. I'm now looking for a 1962 July-Aug t10-D trannie to mate with my "421".

Hugh------

By "...wrong bellhousing (1958)" do you mean that you have a 1958 bellhousing on your 1963? The 1958 bellhousings were cast iron and used a bellhousing-mounted starter.

There was no 163 tooth flywheel. All 1956-62 Corvettes used a 14", 168 tooth flywheel. All 1963-68 Corvette small blocks used a 12-3/4", 153 tooth flywheel.

[Hugh G.]

Re: Bellhousing Depth

You are correct I had a 58 bellhousing and my starter mounted to it. The bellhousing was cast and the flywheel was the 168 tooth. This particular flywheel took a 10.3(?) inch {small} but I replaced the clutch and the starter along with the flywheel and bellhousing.

[Tom D.]

Re: Bellhousing Depth

In addition, I believe the '65 big block Corvettes also had the 153 tooth flywheel.

[Joe L.]

Re: Bellhousing Depth

In addition, I believe the '65 big block Corvettes also had the 153 tooth flywheel.

Tom-------

Yes, 1965 L-78 did use a 12-3/4", 153 tooth flywheel. 1967-69 L-88/ZL-1 did, too. However, the flywheel used for all of these applications was not the same as the one used for 63-68 small blocks. The flywheel was a "lightweight" 12-3/4", 153 tooth flywheel. No other Corvette big blocks used a 12-3/4" flywheel.

[Joe L.]

Re: Bellhousing Depth

Well, sorta.
In 1963 ONLY, the front bearing retainer on 4spds was smaller than 55-62 and 64-later transmissions---------------------EXCEPT, EXCEPT, EXCEPT on 409 cars!!!! The 1963 ONLY 409 cars with a 4sp used the SAME front bearing retainer as was used on 55-62 3sp transmissions. SOOOOOOOOOOOOOOOO, all that is needed to be done to fit a 63 only transmission into a 64-later bell housing is to round up a 55-62 3sp front bearing retainer and install it on a 63 4sp. TOOOOOOOOOOOO EASY!

Oh ya, also, beginning with 1955 cars (pass car, Corvette, doesn't matter), all bell housings (cast iron or alum) are the SAME depth. Think about it------------from the front face of the transmission case to the pilot on the end of the input shaft, the dimension on ALLLLLLLLLLLLLLLL Chevy manual transmissions (3sp, 4sp, doesn't matter) is the same dimension. Thus, the dimension from the front to the rear of all bell housings has to be the same----------------and that includes truck bell housings which were used for 12in clutches.

Tom-------


Like this one [not for sale]

[Tom P.]

Re: Bellhousing Depth

Joe,
That looks like the one!