As jt2ma71 says here, the e-brake shoe has heaps of clearance - just pulled mine apart to check and there's 6mm to spare, so no need for machining there.
This is a good point, as the step goes the opposite way to what you'd expect...... who knows why its there? bloody Subaru....... I'd be wary of machining across the entire surface from the center to the outside edge of that face though, unless you also skimmed the wheel mounting face and both sides of the disc surface to ensure they all remain true - otherwise the runout could be a problem. I'm sure your machinist only took down that stepped section though to avoid this. Good info, thanks jt.
I've got some more pics and fitting points that i'll post up once they upload.
I have no doubt it was done right in your case mate, the level of your build leaves no corners cut i'm sure!I've only had about .25" all the way around machined and that's enough. The transition was also beveled to prevent any structural issues. I'm sure everything was done right
^^ This, what is the main concern here? It seems that if one or the other isnt machined then there will be a small gap between the mating surface toward the center of the rotor/hub. However, the outside edge will still make contact. Just trying to figure out how not doing anything in this area poses as a safety issue.Is that a major concern? Also, why better to machine the actual hub vs just the rotor?
Yeah I haveit on mine :/
Ahh, that makes sense! It would seem that one could kill 2, maybe even 3 birds with 1 stone by designing a 2mm spacer with a .5mm step outer lip that would sit in between the hub and rotor. I wonder if this would cause any interference?Yes, now bolt them down Warped rotor would be the least it would effect it, worst could be cracking...
Hmm, I was under the impression that by bringing the rotor out 2mm it would do 3 things:I wouldn't chance it with a spacer under the rotor... apart from the fact that you'll need to increase your caliper spacer (washer) correspondingly, the chance of getting runout at the disc braking surface is not worth it, and also changing (moving) the contact surface for the internal drum e-brake, albeit probably not enough to matter.
It would however eliminate the need to clearance the backing plate where it touches the rotor.......
If you're gonna bother with machining a spacer, you may as well just machine the rotor or hub though yeah?
BTW: your spacer wouldn't need a step..... it only has to sit inside of the stepped section of the rotor, that's plenty enough contact for the hub (no less than the donor Subaru Impreza has in any case)
You are correct, the caliper spacing would have to correspond with the rotor. I was thinking of it backwards!That's a cool flex-arm setup for the dial-guage in that video link, sure beats using the magnetic arm standard versions!
Sorry, didn't measure the diameter at the step in the rotor before mine went together.
I think you'll find that the caliper spacer thickness will have to be increased by the same amount as the thickness of your rotor spacer that you are planning to use, not the other way around.
I don't see any major issues with what you are planning to do, it makes some sense if you are not changing wheel bearings anyway (as I was) so saves extra dis-assembly.