I have a 1967 convertible Bird with a completely rebuilt 326 bored .040 over with stock cam and a Holley 4 barrel. I also added a rebuilt TH350 trans in place of the original Powerglide. I am looking to change my rear end gearing to achieve a bit more torque. I need to know if my 2.56 ratio XB rear diff will accept a gear change to 3.23 ratio. Further, can I use this axle and housing and turn it from an open diff to a posi rear? Any info regarding this change and suggestions about parts is greatly appreciated.
You can use your housing. If you were just changing gears, then it would not be a straight gear swap with the series carrier you have without a spacer. If you are switching over to a traction lock carrier, then you will have no problems with the 3 series gears in it without a spacer. Auburn is one company that come to mind but there are others that make what you want.
I thought there were no aftermarket BOP posi units for anything numerically lower than 3.36. You might need to find a good used BOP Safe-T-Track unit for 3.23's
I did a lot of research on the posi kits when I did mine last year. Like Bob said, I could not find a 3.23, but did find a 3.36. I’d like to have a bit taller when I’m on the highway, but it’s a lot of fun on the back roads!
