Technical 4 speed Toploader Questions

Hey fellas

Wanted to pick your brain on some 4 speed toploader questions. Reached out to David Kee and Dan Williams but sent to voicemail.

Recently picked up a big block toploader without a tag. Turns over nicely. It has the 3/4” input shaft snout verifying its from a BB, close ratio with the 28 tooth second gear, and 28 count output spline. My plan is to use this with a small block ford 289/302.

1. Wanted to confirm the input shaft is a direct swap over from a BB 1 - 3/8” to the smaller 1 - 1/16” for my use in a SBF?

2. Tranny also has a broken ear. Any main case from 1964-71 and a 4 speed will swap over correct?

3. Anybody have the CD that Mark with from toploader heaven used to offer for rebuilds? Willing to compensate plus shipping. Planning on doing the rebuild myself, open to some suggestions of other resources as well. Planning to get a rebuild kit from David Kee or Dan Williams. Have the tools needed.

Thanks.

Frank

 

Yes, the pilot bearing protrusion on the BB and SB differ in length. Not all BBs used the 1 3/8" input, so the BB pilot length doesn't mean it's a 1 3/8" input. The big shaft was used on the 428 and 429. The small shaft on the 390s. The big input shaft was used with the 31 spline output. To go from the 1 3/8" input to the 1 1/16" requires a change in front bearing retainer. Any 8 bolt main case should work.

 

I would add, all 1 3/8's input are close ratio.

 

One thing to watch out for is the FE trans has a shorter pilot bearing shaft. It's not long enough to fully engaged the pilot bushing, and the bushing can 'wallow out' because of that. The fix is a steel bearing; a NTN 6003 LLBC3/5K will work, and some vendors sell these (or similar). Not a bad idea in any case...

And IIRC, you can use a later cast-iron 4-speed 'overdrive' case in place of the regular 4-speed case, that may be easier to find (and cheaper). And the '64 cases were the '49-64 narrow trans pattern, you want a '65-up case (unless you're doing a 5-bolt SBF).

 

I think I remember that the 390 1 1/16 input shaft was about 1/2" shorter than a small block 1 1/16 input shaft. Can anybody else confirm that?

 

EDIT: It sounds like Crazy Steve has me covered - seconds before I posted my last post...

 

There may be an issue with the reverse idler shaft between the two transmissions.
Years ago I swapped the guts from a SROD overdrive to a toploader case and that shaft was about 3/8" longer in one of them, I don't recall which.
This change may have been made in the earlier cast iron overdrive.
I made a bronze spacer to address the difference.

 

Great! Thanks gents. Going to start ordering parts and looking for a main case.