Wilwood Disc Brake Issue

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Ricks70Duster340

Ricks70Duster340

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I have been using the 73 disc setup from Dr Diff for a year or so. Biggest issue I've had is the passenger caliper seems to not fully release and the discs drag.

While troubleshooting a front end noise, I went ahead and replaced the front brakes with Wilwood discs & kept the MC as it was. Had no problems with the installation but those brakes don't have near the stopping power of the Dr Diff units. As always with brakes, I cleaned the rotors before putting the discs into the caliper and made sure there was no contaminants on the pads. When I apply the brakes they act like they are wet and not grabbing the rotor very well. No leaks out of the calipers or anywhere else so not sure what's going on.

Kinda at a loss here.
 
Are the pistons in the calipers a lot larger than the Dr Diff ones were? Maybe your master is pushing enough fluid to move the pistons in the new calipers.
 
Should be improvements obviously. I have basically the same set up it sounds like (Mr disc rear and wilwood front). I drove my avatar pic car down the road for first time this past week and have similar issues. As I understand the compatibility between MC (mine is manual), wilwood and Mr B is supposed to be ok (TBD in my case). I have had in some occasions just had to bead lines again after a couple drives or found a tiny leak which was hard to find or in one instance I had to install an adjustable proportioning valve. My issues are perhaps just break??… not sure yet. Or growing pains choosing to go manual breaks.:realcrazy:

Good luck.

Some real mechanics here likely have better ideas and things to check. Good luck.
 
With the RF dragging issue - could be an obstruction in the hose that feeds that caliper, acting like a check valve and not allowing fluid to "vent" from the caliper. If the rotor seems to be dragging when you try to turn it by hand, remove the bolt and hose from that caliper and see if it frees up at all. If it does, replace the hose.
 
You need a 15/16 master for those brakes. The smaller the master cylinder piston the less pedal pressure you will need. What size piston is your master cylinder would be the first thing to check.
 
Be nice to know which Wilwood kit you put on, too. 6 piston with 15" rotors? Or 10" solid rotor drag race setup?
 
Oldmanmopar said:
You need a 15/16 master for those brakes. The smaller the master cylinder piston the less pedal pressure you will need. What size piston is your master cylinder would be the first thing to check.
Click to expand...
I am using the OE style front disc MC. Got a replacement from RockAuto and I believe it has a 1" piston.
 
Could be they just need to be bedded in.

But I suspect the biggest issue is you lost a fair amount of piston area with the new calipers. Depending on which caliper you had (2.6" piston or 2.75" piston) you lost either 10% or 23%. You didn't say what size rotor you had either so hard to say how the 12.19" rotors changed the leverage.

Best guess is you got used to a big piston caliper and lost a fair amount of piston area so you need to apply a fair amount more leg pressure to get back to where you were. A smaller bore MC would help that.
 
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