jasycZ28

I have everything cut and everything was going good until. I mounted the pad abutment bracket to the bracket (bob bishop's bracket) and it hits the rotor. I have the lock washer and the regular washer on it. I was thinking the piece that holds the brake pad could be bent or something but it was the same on both sides. Any help would be great. I was using this site as a reference http://www.camarossworld.com/Technical/Brakes/C5/
and this one
http://chris96ws6.mtfba.org/c5brakes...stallinstr.htm


can someone please point out something really stupid I am doing so I can finish.

trackbird

How is it hitting the rotor? The front (outside face visible through the wheel) or the inside of the rotor? Could you post pictures? Did you put washers between the PAB and the bracket, or behind the whole assembly? Any info would help us help you.

Also, do you have a few lug nuts snugged down on the rotor (just by hand), if the rotor is not sitting squarely on the spindle, it may hit the PAB, but be fine after you put the wheel on. Just asking.

lateapex

First, you should be using the printed instructions included with the brackets. They have changed slightly since my brackets are now aluminum and use different mounting hardware. The online instructions on Chris’s web page are for my original steel brackets.

Second, you would be better served by using the online install guide for LT1 cars if your car still has LT1 steering knuckles:
http://www.projecttransam.com/projects12.asp

Trackbird’s questions are exactly what I would ask. The only other time someone had this problem, they simply pushed the rotor against the hub, without snugging it up with lug nuts (if your lug nuts are not open backed, you may need to use washers under them so that they apply clamping force to the rotor). In 200 sets of brackets, I have not shipped one out of tolerance. I measure the length of both ends of the standoff on each bracket before shipping.

If snugging the rotor doesn’t solve it, you may contact me at: lateapex at charter.net

Bob Bishop

trackbird

Bob, I was going to pm you a link to this if my ideas didn't fix it, but you found it first. I am interested to see what the resolution is on this one.

jasycZ28

I am not saying your bracket(Bob) is the problem. It kinda looks like the PAB is the problem. I am going to go and buy new PAB's and rotors and if that doesn't work I will put pic's up for everyone. And yes I was using this site also I just forgot to list it.
http://www.projecttransam.com/projects12.asp

lateapex

I would not buy new PAB’s yet. Even if you bought used C5 parts, it is doubtful that someone would have bent 2 PAB’s exactly the same. If you want to email me, I will send you my phone # and I can walk you through this step-by-step. I have a lot of experience with C5 brake installs.

Just to be sure you understand, my bracket ONLY adapts C5 parts. You cannot use the LS1 PAB’s with my brackets. The PAB mounting holes in my bracket are 14mm diameter to accomodate the included 14mm bolts for the 14mm C5 PAB threads. If you use 12mm LS1 diameter bolts in order to use LS1 PAB’s, everything will be out location-wise, and also, will not be able to be adequately torqued.

Bob

jasycZ28

The outer upper part of the PAB would hit the rotor. What I had to do was put a washer the same size as the washers given for the brakets (Bob's) on the top side only between the braket(Bob's) and the PAB. Everything is working fine for now. I haven't driven it yet because I am doing the 1LE shocks and springs as well. So tomorrow I will have everything finished. And I will let you guys know how it went.

Now I am NOT saying that Bob's brackets were the problem. I don't know what the problem was. My Z likes to have every problem in the world. It seems like there is no simple job on my car.

If anybody wants pics I can email them to you. And if someone wants you host them be my guest.

jasycZ28

Just was reading what trackbird wrote a little more in depth and he asked:

Did you put washers between the PAB and the bracket, or behind the whole assembly?

Should I have put washers between the PAB and the bracket? I did on the top to keep the PAB from hitting the rotor, but should I of done this from the beginning. I thought I read the instructions very well and I didn't have any washers left over. Just was wondering if I need to put a washer on the bottom as well?

lateapex

There should not be ANY washers between the steering knuckle and my adaptor bracket, or between my bracket and the PAB. If you drive the car like that, the 10mm bolts will probably loosen up after the lower edge of the washer you put there creates an indentation in the aluminum bracket.

Also, spacing my adaptor out from the steering knuckle will greatly reduce the friction area between the steering knuckle and my bracket. This friction, created by the clamping force of the bolts, is what resists the torque of brake application. If you minimize it, the torque will eventually overcome the resisting friction and the braking torque would be applied directly as a shear force to the bolts. That would be bad. And obviously, if the bolts loosen, then your wheel bearing is loose also.

I have never heard of the wheel-bearing-assembly bolts loosening, when everything is sandwiched together FLAT, as GM intended.

I sent you my phone #. I suggest that you CALL ME, or have a professional mechanic perform the installation.

jasycZ28

I don't have any washers on the steering knuckle. I have the lock washer and the regular washer on the bracket for the bolts that connect your bracket to the PAB. Then I had to add another washer between your bracket and the PAB on the top side only. This is the only way it would work.

lateapex

The supplied flat washers are .110” thick. If you need a washer that thick to correct for your offset, then you either have bent steering knuckles or, as the instructions caution to check for, you have a protrusion on the back side of the steering knuckle keeping my bracket from seating flat. From the direction of the correction you are trying to make, it would be a protrusion around the top of the adaptor bracket. There is a boss in that area on early steering knuckles to index a small bracket that locates the ABS wire. My bracket should be located just underneath that boss. The bottom of the boss should have been machined flat after casting. Every early LT1 knuckle I have seen had that additional machining step. Later LT1 knuckles eliminated the boss from the casting.

In any case, I would not drive the car with that washer you inserted. I would find the cause of the offset and correct the root problem.