hi Does any one know what size axels to use in my stuation I have a 914 with a 964/3.8 915 trans with a wave track course spline, flipped ring and pinion ,108mm trans flanges course splined 6 /10mm bolts and 911 stub axels also 108mm 6/10mm bolts . thanks for any info Slammin

Empi and Swayaway both make one in the size you need. Others on the board would know better than I. Hopefully they chime in.
Matt

Sway-A-way axles part number 2420 20.25” custom 930 axles is what I used with my 108mm CV's and stub axles.
PMB sells the sway-a-way axles and the lower cost empi version.
https://pmbperformance.com/collections/pors...rear-axle-axles

I have 914 cv axles in my 3.0 with 915. fit perfectly with the smaller 914 sized output hubs

Steve has it right.