Series 1 vs Series 2 Rear Axles
 

I searched a little bit and didn't find what i was looking for exactly. Besides the Series 2 Axle Shafts being bigger, does anyone have any information on how much stronger they are than the Series 1 and if they are a direct fit? Im assuming they are swappable, but you know what assuming does. Im in the middle of swapping rear gears, and if they are a significant upgrade and bolt in, Im going to do it while it is apart.

I am wondering the same thing. Someone must know.

If you're looking for stronger axles, have you thought about these? https://black-halo-racing.myshopify....ucts/bhr-axles

You would need to swap your CV joints over to the BHR axle shafts, but I would expect them to fit up like the stock S1 axles.

S1 and S2 cars use the same hubs, so at least the outside end of the axles should bolt up if you stick with stock S2 axles. Not sure about the inner end. You may want to try hitting up one of the SARX guys (9krpmrx8 is one) for more clarification. Or maybe the guy who tried swapping an S2 drivetrain into an S1 shell. Here's his build thread: https://www.rx8club.com/rotary-swaps...-my-s1-261187/

Ill read that thread. And I have seen those axle shafts. But I'm hesitant. I have been meaning to email them because I'd like more info on there strength. Reason I say that is, I have been told by Strange and Mark William's that the shaft size needs to increase from spline to spline, just changing the shaft size behind the spline and using a stronger metal doesn't do very much. So they say. Driveshaft Shop said they didnt make axles shafts for the rx8 anymore and had no desire to. All they make is some 1000hp+ kit that is complete axles and hubs and stuff. 9krpmrx8, that's Scott isn't it? I think it is, may have to hit him up as well if he doesnt respond to this thread.