After a few of our LS1 kit customers ran into issues using our E36 T56 driveshaft, which is set-up for the more common 4-bolt BMW rear axle input flange, we noted that some 1995 M3 models had a 6 bolt drive flange. After some research was done we realized that the best fix was to use what all non-M E36 models and all other E36 M3 models BMW used - the 4 bolt axle drive flange. We now sell these kits that include a refurbished 4-bolt flange, a new pinion seal and new pinion nut retainer ring - everything needed to swap out your 6 bolt flange to a 4 bolt. BMW doesn't sell the E36 drive flanges anymore so these are restored 4 bolt flanges - bead blasted, inspected and repainted. Please ship us your old 6 bolt flange back (we avoided core charges) as it helps us locate more 4 bolt flanges.
The 188mm ring gear (all E36 6 cylinder + all USA M3s) housing is otherwise identical between the 1995 M3 model and all others. Swap out this flange and you can use our one piece aluminum driveshaft, otherwise you can make a custom driveshaft yoke (more power to ya). Is the 4 bolt flange as strong as the 6? We haven't been able to break anything on the 4 bolt rear axle on our E36 LS1 car after 2 years of autocross, street and track abuse utilizing 315mm R compound race tires.... so yea, its plenty strong.