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View Full Version : 1le upgrade done, More Rear Brake Power now?



stangs400
09-17-2010, 03:26 PM
so I just finished the brake upgrade on my 71' TA, using the wilwood dual piston d52 calipers, bled the front and took it out, and the drivers rear tire locked up before stopping, so i take apart the rear and readjust both drum brake (both are all new), and take it out again, also rebled the fronts thinking there still might be air in the line, nope. The rear tires are not locking up anymore, but they have way more bite than the fronts do and lock up before the fronts. Do I need an adjustable proportioning valve?

NOGO
09-17-2010, 03:35 PM
What MC and proportioning/metering/combination valve are you currently running?

Skip Fix
09-18-2010, 06:26 AM
My 78 new from the factory would lock the rear on hard braking esp in a turn. An adjustable prop valve helped.

We had a discussion awhile back about if the D52s are actually an upgrade over a big single piston factory caliper from a sq in piston standpoint.

It might also take awhile to bed in the new front pads. Years ago when I swapped semi metallics on my TA's front it took ALOT fo stops for the fronts to even work.

stangs400
09-18-2010, 09:26 AM
Yeah after i did a self alignment on it, i drove it around lastnight, and now the rear dont seem to be locking up at all, but still have more braking power than the front, and also the brake pedal literally now has to go almost to the floor to stop the car. I found myself downshifting to help slow the car even from a cruise speed. so what might be the next step, mastercylinder? I believe its stock

BonzoHansen
09-18-2010, 12:36 PM
Which D52s did you get?

Apogee
09-19-2010, 01:22 PM
Which D52s did you get?

To add to Scott's post, there are four piston/rotor configurations of the Wilwood D52 calipers, with two piston sizes and two rotor thicknesses as noted below. I think his concern is that maybe you have the smaller piston calipers, typically reserved for rear applications, mounted in the front.

#120-10936 2.00"/2.00" piston, 1.04" rotor
#120-10937 2.00"/2.00" piston, 1.28" rotor
#120-10938 1.25"/1.25" piston, 1.04" rotor
#120-10939 1.25"/1.25" piston, 1.04" rotor

Also, what pads are you using? The Wilwood pads should fit into their D52 calipers without any issues. Other D52 or D614 pad options from various manufacturers may have fitment issues between the dual-pistons of the Wilwood calipers and the rivets used to hold noise shims to the pad backing plate. This can cause the pads not to sit flush against the pistons in the calipers and while I wouldn't expect it to reduce your brake torque to the extent that you've described, it certainly won't help your pad wear.

Tobin
KORE3