I'm going to be throwing rx8 gears and an e-shaft into an S5 motor. I know the 8 gears take larger thrust bearings then the second gen 13bs. I was wondering, what all do I need to change, specifcally, will the front counter weight need to be swapped for a 93+ one because it holds the trust washer? Any way to avoid this? like using the larger thrust bearings only on the gear side of the thrust plate and the smaller ones on the counter weight side? Do i need to use a different thrust plate? How do you make this set up work? Thank you.

I haven't stacked the parts to see but I don't see why you couldn't use the large bearings on the inside and the smaller ones on the outside. But really just pick up and FD front weight and be done with it. I had to buy one for just such an occasion and found it for $20. Might as well take full advantage of the better design.

The only issue I have with this is i curently have a factory balanced motor (from an auto) and the counterweights you buy arnt balanced in anyway. What is the advantage of the larger thrust bearings?

easy.. get it all balanced https://www.nopistons.com/forums/pub...IR#>/happy.png , your obviously building this engine for performance, so you should ideally get it balanced , factory balancing can be average at times and throwing new parts into the mix and guessing it should be ok is asking for trouble, not to mention the rx8 shaft is lighter, would also pay carefull attention to bearing clearences using this shaft . Cant really comment on the larger thrust bearings apart from spreading the thrust load on a larger face surface would possibly lessen the chances of wearing the thrusts out quicker and causing engine damage, would imagine the thrust end play should be similar between the two engines

i did rx8 gears in my fd motor, but used 8.5 rotors from an s4 t2. in doing so, the s4 front counterweight was used and i made simple work of it all by using the thrust plates, washers, needle bearings, and spacer from an fc motor...piece of cake.



if you're looking to go the other way, use the plates, washers, spacers, and front counterweight from an re, rew, or renny engine (front weight would depend on what rotors you used....use the weight from the matching rotors) so if you're doing an s5 motor with 9:1 compression, just steal the whole front stack from an re or rew motor.

That sounds like just what i'm looking for. Was the only part you used from the larger rx8 front stack the thrust washer that fits in the gear? or did the FC one soemhow fit?

you know honestly...i can't remember. LOL but the motor still runs, so whatever i used ended up working https://www.nopistons.com/forums/pub...#>/biggrin.png



i think either one should be fine, just as long as you don't use the big needle bearing with the small washer and spacers.

Thank you everyone, i'll post back with what I did and how it runs eventually :-)

Hey, I'm doing a similar project. GSL-SE rotors and front weight with RX-8 shaft and gears.



I just need to confirm I understand what's going on before purchasing the Renesis parts. Can I use the whole GSL-SE thrust assembly?

Can I use the whole GSL-SE thrust assembly with an RX-8 shaft and gears??