Hey,
I'm starting the build up of my motor for my widebody FB project.

The motor I am planning to build is a S5 block. I'm going to use S4 low compression TII rotors, new rotor housings, atkins seals, OEM apex seals. But here is where the question comes in, since RX-8 parts are much cheaper and seem to be a excellent alternative to TII parts how far can you go until the motor will need to be balanced?

I was thinking of going with a RX-8 eccentric shaft (I read its sized half of a thou different? It'll still work fine?), with S4 rotors, RX-8 hardened stationary gears. Then would I need to get the motor balanced because of using different components than what the motor was made for? I'm just wondering what the fine line that defines when a motor needs to be balanced is.

Thanks
Dan_s_young

 

as long as your rotors and counterweights are matched, you should be fine. if it's a hodgepodge of parts or if you're just a stickler with a few extra hundred dollars in your budget, then you can have the entire rotating assembly done - clutch included. however, as i said, with parts that are already matched, you should be fine.