MTFCA Forum

Can the smaller brake drum in an earlier transmission be replaced with the larger 1926 brake drum if you use the 4-dip crankcase oil pan or
does the entire transmission have to be replaced?

Bill

You also need a late Hogs Head. Mounting ears need some grinding to fit or removed completely for a clean look.
The pedal shaft is in a different position to center the band to the drum.
The earlier pedals can/should be changed to match earlier floor board slots.
No biggie since you likely need to replace the internal low cam, worn shafts & O-ring/seal pedal shafts.
Output plate is different, but modifiable. Mag post is different also.

Hi William,
Are you going to the late larger drum to get more brake or because you need a drum and a large one is what you have? If it's the latter
then you can cut the large drum to the width of the small drum on a lathe so you can use the small drum bolts but leave it as long as the
small drum & plate where. then you can use the earlier hogs head if you don't have the later hogs head. If you use a 4 dip pan with no
bolts in the block be sure to get the pan stiffeners, as I understand the 4 dip pan is not as strong as a 3 dip.
Craig.

"I don't make jokes. I just watch the government and report the facts" - Will Rogers

Hey Craig and Speedy,
Thanks for replies. Right now I have a 1922 engine that came with my 26 coupe when I bought it. I have bought a 1926 engine block and am going to rebuild it to replace the 22 engine. I was hoping that I could put the larger brake drum on the older transmission before I go looking for one to replace the small drum. I do have a 26 hogshead and the 4 dip pan so I am good there. It starts to get a bit pricy for new drums and rebuilt transmissions but it sounds like what I want to accomplish is possible.

Bill

Just did and done before. You need the right driven plate too.
If you need transmission parts, I am in Birmingham Al. Have lots of used, NOS and new stuff. Let me know if I can help. Thanks Dan.

Hey Dan,
I will get in touch with you and might take a drive over to see what you have.
Can I email you from your profile?

Bill

Try but here is email.

One more bit.
4 dip pans are weak, that is why the two bolts at top of hogs head and the braces there and under the lip of pan. I would not use 4 dip on early bock. But that is me.

As Dan said, the wide drum and the driven plate are drop in fit. No alterations needed. Wanting to use a wide band on that drum leads to multiple changes.
Using a wide drum on an earlier transmission is a good idea. Finding an early drum and a matching driven plate is difficult. Mating an early drum to another driven plate will often lead to compromises, as the edge of the driven plate forms part of the brake drum surface. Any discrepancy in the diameter of the two will mean a brake drum surface with a step in it, akin to a drum worn by steel band rivets, but with sharper edges.

Allan from down under