Z32 brake problem!!

[Bullet01]

Ok, bare with me on this story.

I changed over to Z32 26mm front brakes on my old S13 hatch that I use to have. Everything felt great and I didn't even need to upgrade to a Z bmc or Z rear setup. Well, I sold that hatch and swapped over my brake set up along with my 5 lug hubs to my new S13 coupe. When I installed them, the brakes didnt feel strong and the pedal had some play. It didnt bite or stop hard. My 97 sentra stops a lot harder than this car so I was really disappointed. Also, I noticed my rear pads weren't making full contact with the rotors. This was strange to me since I never had this problem with my old hatch. Both cars are 5spd with no ABS.

So at first I got new Hawk pads along with new rear S13 calipers and rotors since the old ones seemed to be the original and possibly worn out. Well nothing changed and Im still not getting full rotor contact. I even had a shop bleed the brakes. :confused:

Then I bit the bullet and went for the Z bmc upgrade thinking this was the problem. I installed it (pain in the dick), and again make brakes dont get full grip. Everything is bled correctly, even the bmc and all the calipers have speed bleeders now. However, I did get more stiffness in the brake pedal but it doesnt have a lot of give. I press the brake pedal and when i feel stiff contact, its only for a very short distance and I cant press down anymore to get the car to stop on a dime like it should. The rears still dont get full rotor contact in the back and when I try to power stop, only the front passenger locks up.

I searched for solutions and im stumped. Could anybody shed some light or give pointers? I included pics of the rear rotors to give you and idea of what im facing.

Passenger rear
http://i51.photobucket.com/albums/f392/bullet01/Coupe%20Murder/2011-06-18_14-13-25_389.jpg

Driver rear from the inside.
http://i51.photobucket.com/albums/f392/bullet01/Coupe%20Murder/2011-06-18_14-14-46_161.jpg

[nismolvr]

sounds like bad rear calipers , need to be rebuit.Your car is front brake bias. Very dangerous. rebuild rear calipers or buy rebuilt ones and change brake booster to a z32.Try that see what happens.

[Bullet01]

Rear calipers are brand new.

[KiLLeR2001]

Make sure the slide pins on the rear caliper brackets are not getting stuck, causing the caliper to not be able to move in its full range of motion. You need to pop them out and grease them up well.

[nismolvr]

Make sure the slide pins on the rear caliper brackets are not getting stuck, causing the caliper to not be able to move in its full range of motion. You need to pop them out and grease them up well.
^^^^^
yup, good call judging from your rear rotor pic its obvious one brake pad is only making contact,other inner pad isnt touching rotor at all.

[Bullet01]

I did check that during my last install n the pins are lubed up n travel freely. The pins are also new. This y im stumped. Cud the front calipers have anything to with the way the rears act?

[nismolvr]

I did check that during my last install n the pins are lubed up n travel freely. The pins are also new. This y im stumped. Cud the front calipers have anything to with the way the rears act?bleed system again, in this order , RR ,LR ,RF, LF.

[Bullet01]

Yea I bled it like crazy. Gave it 3 passes and everything was clear.

[AS240]

i had the same problem. i had to get a vacuum hand bleeder to finally get all the air out of the system. i have z32 brakes all around and a s13 abs booster

[Bullet01]

I was thinking about upgrading to an abs booster but doesn't that just help pedal feel rather than clamping force for the calipers?

[nismolvr]

i had the same problem. i had to get a vacuum hand bleeder to finally get all the air out of the system. i have z32 brakes all around and a s13 abs booster
Now that were on the subject , I know i have to do this to mine . I too have to vacuum bleed my complete z32 brake swap. using 1" BMC ,z32 brake booster, z32 everything front and rear.I too bled the hell out of it. and it seems that its heavily front bias. I mean it dips forward hard when i modulate anywhere near half way braking point. Wich leads me to believe , Im suffering from same problems.(sorry for thread Jacking).I think this is our problem definetly.

[tabasco122]

looks like the caliper is crooked slightly. it contacts the outside in front of the rotor, and the inside on the back of the rotor

[Vernal]

Pin on the pad is lined up with the slot in piston? How tight is the piston adjusted? rotors in spec?

[LayNLow]

Then I bit the bullet and went for the Z bmc upgrade thinking this was the problem. I installed it (pain in the dick), and again make brakes dont get full grip. Everything is bled correctly, even the bmc and all the calipers have speed bleeders now. However, I did get more stiffness in the brake pedal but it doesnt have a lot of give. I press the brake pedal and when i feel stiff contact, its only for a very short distance and I cant press down anymore to get the car to stop on a dime like it should. The rears still dont get full rotor contact in the back and when I try to power stop, only the front passenger locks up.
You really need a Z32 (I think auto 240 or abs 240 will work) brake booster to make the pedal not hard as a rock. I had the same problem with my Z brakes. But I have the whole Z brake setup. All calipers, parking brake, master cyl and even a brake booster. They feel Awesome!!! Minus a small problem with the ebrake I have yet to figure out.

Your photo, if from the same caliper, looks to have either a crooked caliper, or cocked pads. Some rear pads have nubs on them. Match these nubs up to the piston, or just file them off. If that doesnt fix it then...
Check the caliper sliders (the word for them slips my mind, this is the part that has the channel for the pads to slip into, this may be the right word though) and make sure those are not bent. (most calipers wont come with these when bought from a parts store) Check for anything between the calipers and the spindle that would cause them to sit crooked. Could also check and make sure the caliper mounts arent bent on the spindle.

Is the wear the same on both sides? Where each side has the outside wearing different than the inside? Or is it just isolated to one corner?

[Bullet01]

On the passenger rear, i only get partial contact on the outside and full on the inside. Driver rear, i get full contact on the outside and partial on the inside. I will check the pad nubs n try to align them with the piston.

[lazysk8er2]

does ur new car have abs?

[Bullet01]

does ur new car have abs?

No it doesnt

[Bullet01]

Well i think i solved the problem somewhat. I aligned the pistons on the rear caliper to fit the nub on the pads. This helped a lot with the brake response n also i get full contact on the insides of the rotors. However, i still dont have full contact on the outside of the rear passenger rotor. Guess the one pad is a lil uneven but they only have like 100-200 miles on them.

[Bbsalexaz]

Did you lube the metal on the sides of the pads? I concur with the booster upgrade.