Dr Diff 13" PBR kit and Year one 17" rallye wheels

[Aracer]

12.88" is dam lose to 13".  12.88" kit fits into 15".  The 14" is a no go. But we need the facts.

[60K T/A]

I spoke to Cass and told me the 13's and Cobra calipers fit. Unless things change (unless some thing better comes along) this is the route I'm currently taking.

[7212Mopar]

Do you have the kit? Some quick measurement is very much appreciated.

[60K T/A]

No. Right now I'm starting to gather info before I make a purchase.

[RCman]

Okay so I pulled a wheel off and measured.
I have 7/16" of clearance from the body of the caliper (closest to the outside of the car) to the wheel, which is the smallest diameter portion. That part of the wheel has a diameter of 15-3/8". Double checking my measurements the caliper to the center of the wheel hub is 7-1/4". This seems to verify as (7.25+0.4375)*2 = 15.375
The step in the wheel jumps to 16-1/16 and then tapers larger to the inside of the wheel. This setup is necessary to maintain the same clearance for the fins on the caliper, however one you easily reduce those fins on the caliper to clear the wheel if needed.

With the smallest diameter that 7212Mopar measured being 14.75" the brake package might just clear but a few sheets of paper. Haha. Comparing with my measurements above you'd have about 1/8". Then again we both measured with a crude tape measure and not something all that precise. Clearance is clearance right?

I hope that helps. If you need something else let me know.

[7212Mopar]

RC man, thanks for taking the time. Your measurement would really help. I think it might just clear since the caliper is further away from the hub, probably not my much. I am going to check my measurement one more time to be sure.

[Mopar Mitch]

With the concern of very tight fits, the thickness of tape weights can be an interference to the caliper and rim.   I'm planning an upgrade from my stock 10.75 front discs... still to keep my 15" and 16" rims.    Mopar rally 15" will not clear over Viper calipers and 11.75" rotors (I recently tried this).... and tape weights also hit the Viper calipers on another set of 15" rims.

IF I ever get new rims... they'd be 18" diameter (wider choice of 200 TW tires)... then and only then would I step up to larger ~13"-14" discs.... but then never be able to run my 15-16 rims.

[60K T/A]

In your Spare time just replace your 13-14 inch disks back to 10.75 and run your 15 inch ralleys

[60K T/A]

Hey RCman, where did you pick up those slotted rotors?

[RCman]

Hey RCman, where did you pick up those slotted rotors?

They came in the complete kit I got from Cass (link), I believe they are '95 Corvette 13" front rotors.

[60K T/A]

With the concern of very tight fits, the thickness of tape weights can be an interference to the caliper and rim.   I'm planning an upgrade from my stock 10.75 front discs... still to keep my 15" and 16" rims.    Mopar rally 15" will not clear over Viper calipers and 11.75" rotors (I recently tried this).... and tape weights also hit the Viper calipers on another set of 15" rims.

IF I ever get new rims... they'd be 18" diameter (wider choice of 200 TW tires)... then and only then would I step up to larger ~13"-14" discs.... but then never be able to run my 15-16 rims.

You can use Dyna Beads instead of wheel weights if clearance is an issue.

[7212Mopar]

I took some more measurements on the inside of the Year One 17" Rallye wheel. I took two 12" straight edges to the inside of the wheel to make contact and then measure. These measurements should be a little more accurate than using a tape.

At the hub of the wheel, I measured 14-7/8"
At 2" above the wheel hub, I measured 15-1/4"

Hope this help.

[7212Mopar]

Dr Diff confirm the 13" kit should fit the YO Rallye. I placed the order already and will mark it up once I receive.

[Pentastarnut]

^ good info  i'm watching for the update

[7212Mopar]

I got the calibers on Friday and today I mocked up the Dr. Diff 13" PBR front brake (passenger side) to check clearance on my YO Rallye 17x8 front wheel. I managed to use the wrong side bracket as the pin should be on top per instruction but should be good for clearance checking purpose. The caliber clears the wheel with about 3/16" to 1/4" clearance and no hit. I hope this helps anyone that might be thinking of the same setup. It will be awhile for my car to be back together so road testing will have to wait. So far setup looks good and the installation is straight forward. One thing to note is I am using the stock 73 knuckle for mock up and it requires some grinding for clearance in order to insert the upper mounting bolt for the adapter to caliber bracket. I have the repo knuckles on the k frame already and a quick look appears no grinding should be required. I need to check that to be sure.