This was supposed to be a replacement (clean one) for the input shaft bearing retainer.

I bought it on e Bay thinking this would work for a big block 70-71' bellhousing. It's
not even the same bolt pattern. What is it for?

First photo shows bolt pattern comparison.
Second is mine on the right vs. the new one I bought.

Here's the listing.

http://www.ebay.com/itm/mopar-nos-833-4-...nc#ht_118wt_895

There are several different bearing retainers. I know the diameters vary, maybe the bolt pattern does also. It is usually helpful to spend some time looking at a Master Parts Book before spending too much money buying parts.

Id guess the EPay version is for a 18 spline 833.

There were two bearings, #307, #308, three retainer sizes, 4.35, 4.80, 5.125. Plus there are size and bearing combos for the 18 vs 23.

I know the 4.35 and 4.80 retainers for the #307 bearing has the same bolt pattern, not sure if the 4.80 retainer for the #308 bearings shares the pattern.

I think that retainer isn't for an 833 of any kind.
That's a real early part number shown in the ad pic, #2606243, possibly 1960 or 1961, a few years before the 833 was introduced.

A 70-71 trans should have a 4.80 retainer for a #308 bearing, there are two, one for an 18, one for a 23.

A Google search using the 2606243 on the retainer indicates it is a Ford/Tremac application.

http://www.google.ca/#q=2606243+retainer

Thanks for the input everyone. I have a lead on a 308/4.080 retainer bearing. But since I have a 23 spline 307 bearing all bets are off until I confirm their interchangeable. Gut feeling says they're not.

Off to Brewers on the phone and hear what they say unless I hear a confirmation here.