I'm going to be putting my motor together next weekend, but I'm wondering if I shouldn't get my rotors clearanced first. My motor is an S5 13B-T with a bridgeport. I'm planning on revving to 8500 RPM without changing anything, but I'm wondering if that will be enough. I think I read that the S5 stationary gears are hardened, but how do they compare to REW gears? I may be able to get a set of them locally. My biggest concern was rotor clearance. I work as a co-op engineer in a large tool&die shop for a factory, and there are some very good machinists who said they could machine/grind whatever I need.

So my question is, should I clearance my rotors incase I want to rev to 9k? Anyone have a technical drawing or detailed discription of where and how much material to remove? Also, will enough material be removed to require the rotating assembly to be rebalanced?

 

I would be more concerned with a proper balancing of the rotors, rather that clearancing them. IIRC clearancing is used for high boost applications where extreme heat in the combustion chamber will make the rotor expand, hitting the side housings. If you are running moderate boost and just want to run High RPM balancing your rotating assembly is the way you want to go.

Edit: As far as the REW stationary gears, I believe they are considered an upgrade for any 2nd gen motor.

 

You can use RENESIS stationary gears, which, if I remember correctly, are the hardest from the factory. You can get them new from Mazdatrix for like $200.

 

as i understand it, the reason to clearance rotors for high RPM is eccentric shaft flex (think of a barbell). i don't know what the RPM potential of a half-bridge is, but if you plan to stay true to your 8500 RPM limit clearance shouldn't be that big of a deal, i'd spend my time on simply balancing everything.

the S5 stationary gears are hardened, but i don't know if they are less reliable than the REW or Renesis gears. what i do know is that there is some fitment or sealing issue when you use Renesis gears on older housings.

 

^ You just have to use sealant where older engines use an o-ring.