Trevor, I've gone through this same thing with my 911 as my 915 didn't come with flanges either.
The 915 flanges are a smaller size than the 944's.
Is your dif fine or course spline inside? Mine is an aluminum case with fine splines from a 79. If yours is a mag case, it should have course splines. If so you can use 901 flanges from a 914 or 901 tranny. Not sure what you can do if they are fine spline.
There is a guy selling 901/914 flanges on ebay for cheap, haven't seen 915 flanges on there.
901/914 flanges have 4 bolts with a pin, you can either put a stud in the cv's or weld and redrill the flanges for another bolt.
|