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Soilsack
11-08-2015, 12:05 PM
About 6 months ago I did a front Z32 brake conversion on my S14. The brakes on the donor car were good and had drilled and slotted rotors with unknown pads. Put the brakes on and had no issues at all. I did not like the look of drilled and slotted rotors so when it came time to replace my rear pads I got Centric Blanks and Hawk HPS pads for the front.

After replacing the rotors and pads I have had a series of problems and I can't figure any of them out.

Installed everything and went smooth. I cleaned the rotors and bedded in the pads. After a couple of days I had a REALLY bad squealing coming from the brakes after they are warm and under 30 mph. I also noticed a "honking" noise coming from the brakes when turning after depressing the brakes. This noise occurs when I do not touch the brakes at all. It sounds like maybe the pad is catching on the rotor for some reason. I assume that it is the brakes because if I touch the pedal when the noise is happening it will stop until my next complete stop.

I had the rotors resurfaced and scuffed the pads with sandpaper. I re-bedded them and the noise was gone. For a day. Now the noises are back.

I have had the car looked at by a local race shop and they don't see any issues. It is NOT a wheel bearing. There is no play in the hub. It is NOT the backing plate or dust shield. I can not figure it out. If anyone has ideas let me know.

I uploaded videos of the issues. Help me out as I am about to just get rid of the Z32 brakes and put OEM back.

https://youtu.be/KcJLyywW9i4

https://youtu.be/6Cu2uDUrMsM

RickBlaine
11-09-2015, 08:06 AM
Stop looking at your pads and rotors, and look at your calipers- specifically the slider pins, as well as the replaceable shims installed on the caliper to accept the brake pad's "ears".

Make certain you have the proper brake lube, and not too much brake lube in those caliper brackets. Too much means the slider pins are not allowing the "retraction" of the inner and outer pads after you take your foot off of the brake.

To me, it sounds as if your inner brake pads are not retracting fast enough AFTER you take your foot off of the brake. Those slider pins are not doing their job. That and check the lube on the brake pad ears and shims.

None of this would be noticeable on a floor lift in a speed shop. Everything would look fine.

What would be possible, but is unlikely, is that the brake pads you have are every so slightly too small for the calipers- perhaps because the previous owner of those calipers may have used a Dremel tool at one point to enlarge the space to receive some other brand of brake pads. But that would be called "pad slap", and you did not mention a banging noise heard only once the first time you brake in reverse, or the first time you brake while driving forward.

Soilsack
11-09-2015, 08:29 AM
Actually, I do notice a clapping noise whenbraking in reverse, never forward though. I thought this was normal. I replaced all of the brake hardware with new OEM and followed the FSM for lubrication. These are Z32 Front brakes by the way. I assume when you are talking about the pad "ears" you are talking about the retainer clips on sliding calipers?

Soilsack
11-09-2015, 08:39 AM
I was thinking of ditching the nissan spring clip and replacing it with a one lb spring on each guide pin.

dbeiler
11-09-2015, 06:33 PM
Are you using the correct rotors for your calipers?

Did you measure to see if they are 26mm or 30mm before ordering parts?

Do all the wheels still spin freely if you jack up the car and pump the brake pedal a few times?

Is a caliper seizing after you release the brake pedal?

Who installed the brakes? Where they careful not to damage the brake hose inner lining by keeping the caliper weight off the brake lines at all times?

Soilsack
11-09-2015, 08:29 PM
Yes, 35mm channel 30mm rotors. Wheels spin free. Light scraping from the pads sitting on the rotors but I have always heard that on any car I have worked on. I can't really see the pistons when pumping the brakes but since I can't hear any additional binding when going straight on the road or on Jacks I assume the pistons aren't seizing. I installed the brakes and no weight was ever on the brake lines. I secured them using bungee cords.