88irocz28

I went to autozone for it and they stock any such thing. Attendant said nobody would have it. Is the kit sold anywhere?

My brakes don't come on the instant I hit the pedal. And when they do they're weak. Is it something with the master cylinder or combination valve, or the booster?

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'88 IROC 305 TPI
Gutted airboxes
160 degree T-stat
Advanced base TPS voltage
Relocated IAT sensor
Momo steering wheel
Ram-air setup coming soon
Flowmaster muffler

88irocz28

Anyone?

wm_sorg

Generally when the master cylinder fails you will not be able to maintain pressure in the break system. For example the break pedal would slowly go to the floor when stopped at a traffic light.

First, I would try bleeding the lines. Also make sure there is no lekage in the system via. wheel cylinders and calipers.

If in fact you need to replace the master, I would suggest just getting a reman of new one. It's not worth the time and trouble to rebuild it yourself.

88irocz28

Could it be the combination valve that's causing the trouble? I remember last year the rear wheels were turning on ice even though I was pressing the brakes with all my strength. Another really weird thing with the brakes is that I can't pump them quickly. The pedal doesn't return quickly enough and it doesn't rise no matter how much I pump. What is the combination valve for? Is it just a fancy name for a proportioning valve? i don't think mine's working right because the rear wheels never seem to lock up. In fact the brakes never lock up no matter How hard i press the pedal. Help me somebody!

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'88 IROC 305 TPI
Gutted airboxes
160 degree T-stat
Advanced base TPS voltage
Relocated IAT sensor
Momo steering wheel
Ram-air setup coming soon
Flowmaster muffler

farm-kid/88camaro

im in the same boat, hopefully we can get an answer cause i wanna get this fixed. The combination valve is the prop. valve.



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________________________
88'Camaro
305 TBI

88irocz28

Come on people, somebody has to know the answer to this!

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'88 IROC 305 TPI
Gutted airboxes
160 degree T-stat
Advanced base TPS voltage
Relocated IAT sensor
Momo steering wheel
Ram-air setup coming soon
Flowmaster muffler

TomP

Master Cylinder rebuild kits are available from places such as http://www.wrenchhead.com , http://www.expressautoparts.com , and http://www.carparts.com . You can also find them thru "real" parts stores sometimes... you won't get one out of a Pep Boys!

-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards

wm_sorg

The proportiong valve is designed to make sure equal pressure is distributed between the two front breaks as well as the rears. In some instances it can send more pressure to the rears to compensate for disproportionate front/rear breaking.

In the case where the rear wheels are turning on ice I would check the lines for blockage.

Interestingly enough, I am tackeling the same issue on my car where the right front is not clamping at all. After replacing the calpiers I still had the same issue.

Now I am in the process of checking the lines for blockage before replacing the valve. I have gathered that the rubber lines GM uses are prone to blockage from the insude out.

Although it is possible that your proportioning valve is bad I would try to see if it is sending fluid to the rear breaks.
Since there is a rubber line in the rear above the axl I would susprect that the problem could reside there.

The proportioning valve is about 89.00 and has to be special ordered.

BretD 88GTA

What condition are your brake hoses in? If they are still the original ones I would replace them, preferably with the Russell braided steel ones.

Also,if you replace the master cylinder I'd get the 1LE version. A friend of mine did this on his GTA along with rebuilt calipers and noticed a nice improvement.