915's Trans side Half Shaft Mounting

bullethole · 09-08-2011, 06:51 AM

I picked up a 915/62 (or 63 its hard to read the last digit on the stamping) as a spare trans while my primary trans is being gone over. However, the "flanges" (I'm not sure what to call these) which allow the half shafts to connect to the trans are larger than the CV joint on my 82Euro SC. This leads me to believe that at one time this trans was in a 3.2 (or its a 915/68). The guy I bought it from is trying to find flanges that are correct for my halfshafts, but as I was thinking about this last night, I'm not sure if the inner shaft diameter and spline count is going to be the same. I could spend a bunch of time removing the flanges from my 83 street SC (the original trans is not readily accessible by me) and trying them, but i'm figuring maybe someone here might be able to tell me if its a direct swap.

Also, suggestions for options (most economical) to address this if the seller can't source the right flange
a) take flanges off street car - car is down until i get the right flanges or original trans back
b) update CV joints on the halfshafts (does this require replacement of the whole halfshaft)
c) get original trans flanges sent back to me (assuming they will work) - I'd actuall prefer not to go this route, as I'd like to be able to just drop this trans in should I need it without having to do any swapping of things.. but if necessary i can do this.

Matt Monson · 09-08-2011, 07:29 AM

The splines are going to be the same. If it's a temporary fix just get your original flanges and put the gearbox into the car. If you want to upgrade as part of this process, then get 3,2l Carrera axles and bolt them in and then use the bigger flanges on your gearbox once it's refreshed.

If you don't use the larger stub axle flanges, sell them. They are worth quite a bit of money. Like $250-300 each sort of money!

Peter Zimmermann · 09-08-2011, 07:38 AM

You need a pair of fine-spline flanges from a 1980 (915/63) through 1984 (915/68). Euro flanges from a 915/62 or 915/67 will also work. You are looking for 100mm diameter flanges, and any of the above flanges will fit your transmission. Another possibility is that your trans is a 915/69, which would have been in a 1984 RoW Turbo Look car fitted with 108mm CV joints/flanges.

bullethole · 09-08-2011, 07:55 AM

Thanks. I don;t think its a 68, the bolts that held the flanges on were finger tight (I know the torque spec is something like 30 inch/lb but thats still tighter than finger tight). My halfshafts are indeed 100mm, and the flanges are 110mm.

I was kind of hoping I could just swap out the CV joint on my existing halfshafts, and just identify the right PN on our hosts catalog, but i guess thats not possible since the recommendation to switch the axle says the whole axle is needed.

Since the splines should match up.. if the seller can't get me a set of correct flanges i'll just get the others sent back up to me to use.

Peter Zimmermann · 09-08-2011, 10:12 AM

Quote:

Originally Posted by bullethole

Thanks. I don;t think its a 68, the bolts that held the flanges on were finger tight (I know the torque spec is something like 30 inch/lb but thats still tighter than finger tight). My halfshafts are indeed 100mm, and the flanges are 110mm.

Be aware that the torque is not 30 inch/lb, it's 32 lb/ft! Assuming that you have the correct bolts, of course.

Peter Zimmermann · 09-08-2011, 10:14 AM

Oops, forgot the pic...the right side flange and bolt is what you need.