New Transmission, old bellhousing for GTA

**kengta** · #1 (**permalink**) 10-14-2005, 09:16 AM

I have a later style Close Ratio transmission that has the smaller diameter input shaft used with the later bellhousing for hydraulic clutch applications that has a smaller oil seal.

I want to fit the trans to an early mechanical clutch bellhouse that takes a larger oilseal appropriate to the larger diameter input shaft of the earlier transmissions.

I can sleave the early bellhouse down, which I am favouring (favour because then a later bell house could be easily re-fitted to trans) or sleeve the input shaft up to accept early large oil seal.

The application is for a GTA (mechanical clutch links) to a 1750 block. I will use a 1600 GTA fly wheel.

Any experience or thoughts out there.

Regards

Ken Geiger

**George Willet** · #2 (**permalink**) 10-14-2005, 09:31 AM

There is a seal that will fit the mechanical bellhousing, and the later input shaft. Take measurement of the shaft, and the outer diameter of the bellhousing seal, to your auto parts store, and they can provide it for you.

**kengta** · #3 (**permalink**) 10-14-2005, 09:55 AM

Quote:

Originally Posted by George Willet

There is a seal that will fit the mechanical bellhousing, and the later input shaft. Take measurement of the shaft, and the outer diameter of the bellhousing seal, to your auto parts store, and they can provide it for you.

**Bill S** · #4 (**permalink**) 11-16-2005, 09:11 AM

I'll resurrect this thread since I'm planning something similar for my 67 Spider this winter. I need to replace the clutch and thought that I would put in a later model transmission at the same time. Mainly because this one has a better 2nd gear and the better (non-rattley) reverse lockout. Ken, if you want to sell one of your spare seals I'd be interested. I'm assuming it would work with my 1600 bellhousing. Also, can I just order a pilot bearing for a 2L crank and fit it to my 1600 crank or will I need to have something turned? Lastly, which rear transmission mount should I use; the one for the later transmission or the more expensive early style (this is a 2L transmission going in an early 105 chassis). Anything else I'm missing? Thanks.

Bill Sinclair
67 Duetto
69 Berlina project

**George Willet** · #5 (**permalink**) 11-16-2005, 11:20 AM

Hi Bill, All the pilot bushing inside diameters are the same.
The transmission mount bushings should go with the year of the car as the rear crosmembers are different heights. An early GTV rear mount on a later chassis will lower the rear of the transmission, and change the driveshaft alignment. I have never seen a need for a "heavier/stiffer" mount either.

**Bill S** · #6 (**permalink**) 11-16-2005, 11:44 AM

Thanks George, that makes sense. Unfortunately it means I need the $85.00 mount instead of the $18.00 one for my 67.
Bill

**kengta** · #7 (**permalink**) 11-16-2005, 12:30 PM

Quote:

Originally Posted by Bill S

I'll resurrect this thread since I'm planning something similar for my 67 Spider this winter. I need to replace the clutch and thought that I would put in a later model transmission at the same time. Mainly because this one has a better 2nd gear and the better (non-rattley) reverse lockout. Ken, if you want to sell one of your spare seals I'd be interested. I'm assuming it would work with my 1600 bellhousing. Also, can I just order a pilot bearing for a 2L crank and fit it to my 1600 crank or will I need to have something turned? Lastly, which rear transmission mount should I use; the one for the later transmission or the more expensive early style (this is a 2L transmission going in an early 105 chassis). Anything else I'm missing? Thanks.

Bill Sinclair
67 Duetto
69 Berlina project

**George Willet** · #8 (**permalink**) 11-16-2005, 05:28 PM

Bill, have you checked with Centerline Alfa in Boulder Colorado for the seal? I do not have the catalog in front of me, but I don't think I pay that much for the early rear mounts.

**Bill S** · #9 (**permalink**) 11-17-2005, 07:30 AM

Thanks George,

Yes, it pays to do comparative shopping! I'm also considering swapping a 115 crossmember for the 105 crossmember as we discussed offline. I mention it here just in case someone reading this thread might benefit from the additional info. I've got 2 or 3 grimey 115 crossmembers laying around and a new 115 transmission mount so, hey, why not? (I record all such alterations in a little booklet that stays in the glovebox just in case someone else may own this car someday.)

Bill