Brake Gurus: Shimming rotor for caliper alignment ... ?

[BTB]

Howdy,

I'm working on my rear end rebuild and have encountered a bit of a blip in the road, as one may expect. I'm mounting up a set of Wilwood calipers using the Chase Bays dual caliper kit. Chase Bays has specified to run the kit without heat/dust shield, but it seems to me easy enough to cut out the shield so that it is compatible with the Chase mounting bracket. Anywho, I got it all cut up and mocked up, everything fits well except the caliper/bracket are now offset by the thickness of the shield (don't have digital calipers with me but around one mil?) such that the bracket/caliper assembly is closer to the rotor. See images below.




My question is: can I shim the stock rear rotor by ~1mm between the rotor hat and hub, to increase this clearance? I would think the stock sliding caliper has enough movement to tolerate this. Just wondering if there are any potential issues to consider. Seems like this isn't a totally unusual thing to want to do ... one thing I thought of is my rear spacer (12mm) will lose engagement with the hub by whatever offset I go with, if I shim the rotor.

Appreciate the input--

Brendan

[sapote]

There are pistons on both side of the rotor, and so as long as the pads are in under the compressed pistons then it should be fine. There is nothing wrong with the caliper is 1mm offset to one side as long as the rotor is not touching anything. but the pads. Don't shim the rotor as it might not be flat.

[ac427]

Does the dual caliper kit allow the use of oem rear caliper for the handbrake?

[BTB]

There are pistons on both side of the rotor, and so as long as the pads are in under the compressed pistons then it should be fine. There is nothing wrong with the caliper is 1mm offset to one side as long as the rotor is not touching anything. but the pads. Don't shim the rotor as it might not be flat.

Yeah, I wouldn't think it would be a problem with the caliper. You're right though, I don't think it's wise to put anything between the rotor hat and hub. Once I get my new rotors (stoptech slotted cryo) this week I'll fit it up and see if there's some clearance between bracket and rotor.

Does the dual caliper kit allow the use of oem rear caliper for the handbrake?

I suppose you could do it that way, though I'm pretty sure the total piston area of the Wilwood calipers would leave you with suboptimal brake balance. The intended use is to run the Wilwood calipers with ebrake, and stock brakes with OE foot brake system as normal. Thinking I might do the 'poor man's bbk' someday and put 986 rear calipers on there to match my front Brembos. OE is more than adequate for now, today I ordered new remanned stock brakes