First Generation Firebird-L Mailing List ......................................................................... Thanks to all for the help so far regarding RE gearing and differential setup. I believe that I've got a good track on this, but wanted to get a little bit more info before proceeding.
3.55 ring an pinion gears are available from Richmond for an 8.2 diameter ring gear for use on 1st gen Firebirds. They are 39-11 teeth, just like what is specified in the '69 manual. Since I have a '69 YC axle marking, I'm assuming that I have a non-locking differential of the 2.78 variety. If I want to change to the 3.55 gears, AND limited-slip/Posi differental, then I'll need to get the ring and pinion gears (10 bolt pattern on the ring gear, I'm assuming), and the differential case that will hold the limited-slip/Posi internals for the 3.36, 3.55, 3.90, and 4.33 gears. Now I know that originals are hard to find, so I've been looking at Eaton (for the entire unit, case/internals), and Richmond (PowerTrax internals, no case). I've also heard that Auburn has the entire assembly, but I have not been able to find a supplier. I checked Summit, and they offer the Eaton and PowerTrax differental unit in the 10-bolt pattern as well as a Company called Motive Gear and Richmond for the 3.55 ring and pinion gear with a 10-bolt pattern. Trying to get an idea of quality of the Eaton Posi/Richmond PowerTrax differentials, and the Richmond/ Ring and Pinion gear sets. Also, just a few questions: 1. My diff and ring gear appear to have the 10 bolt pattern, but what bolt pattern does the 3.36, 3.55, 3.90, and 4.33 have? I see in Summit there are several options for a 12-bolt pattern? 2. There are different spline count options. I cannot find in the '69 manual anywhere where it talks about axle spline count. From the vendors catalogs, I see spline counts of 27, 28, and 30 spline differentals, I'm assuming these are for the different years of cars. Assuming all my parts are stock, what spline count should my stock YC axles have? Thanks in advance for the replies... Don Rogers [EMAIL PROTECTED] ------------------------------------------------------------------------ Submissions to Firebird-L: <[email protected]> Unsubscribe from Firebird-L: <[EMAIL PROTECTED]> Help: <http://FirstGenFirebird.org/firebird/Firebird-L.html> Classifieds: <http://FirstGenFirebird.org/ubb/> Owner Pictures: <http://FirstGenFirebird.org/show/> Donations: <http://FirstGenFirebird.org/store/cart.mv?999999> FGF Merchandise: <http://FirstGenFirebird.org/store>
