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  #1  
Unread 11-29-2017, 01:07 AM
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Default whats wrong with my brakes?

1967 camaro, Running disc brakes on all four corners, Wilwood 6 pistons on the front and 4 pistons on the rear. Stock steel brake lines and Wilwood flexlines. I have a dual diaphragm brake booster. I'm not really sure what master cylinder it has on it though. I'm running a BB 396 with a big cam. The car just doesn't stop quick enough. for all that brakes I got, I feel like the car should stop faster and on a dime . I bought the booster and master cylinder as a kit a while back and I don't remember the specs. I don't know much about brakes and all that jazz. I just remember somebody telling me to remove the proportioning valve and that will solve my problem.

thanks, Albert.
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Unread 11-29-2017, 05:58 AM
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I would suggest reading many of the threads in this brake category, starting with "I give up on bleeding my brakes". Your question seems to be a popular one. If that doesn't work, you need to be more specific on your system, including master cylinder bore size and caliper piston areas. The proportion valve should be there to limit rear brake force only. Removing it will not help overall force, unless it is incorrectly installed. I hope this gets you started.
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Unread 11-29-2017, 07:22 AM
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You mentioned a big cam. Which means you may not have enough vacuum to operate the booster. IIRC, you need around 13-14 inches of vacuum for the booster to work properly.

Something to look into.
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  #4  
Unread 11-29-2017, 10:26 AM
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Agreed, you likely have 10 inches of vacuum or less at idle.
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Unread 11-29-2017, 05:23 PM
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What do you guys recommend me to do?Clueless
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Unread 11-29-2017, 08:12 PM
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Try to find as many specs on your brake setup that you have now. Again, caliper piston area, master cylinder bore size, pedal ratio. You need to know where you are at before you can make a move. Do you have a vacuum gauge that you can check actual engine vacuum at idle? There are also pressure gauges available that screw into the caliper bleeder holes for checking actual brake line pressure. All these things are very important to the diagnosis.
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  #7  
Unread 11-29-2017, 08:12 PM
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Stick a vacuum gauge on it since that is quick and easy and report back
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Unread 11-29-2017, 09:54 PM
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Agreed
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Unread 11-29-2017, 11:08 PM
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I WOULD NOT remove the proportioning valve.... you most likely need that -- and at the very least -- need to understand WHY you don't have good brakes before doing something like that.


You do need to do as suggested and check the vacuum - at the take off port for the brake booster.... at the engine. Or if you have a small vacuum gauge hose - at one of the other ports.

If you don't know how to do this - or don't have a gauge - it's a very simple (therefore should be super inexpensive) to have a shop do it for you.

++++++++++++++++++++

After you do that -- check the brake pedal ratio....

Here's a link to show you what that is:


http://techtalk.mpbrakes.com/how-to-...ng-pedal-ratio


+++++++++++++++++++++



Next --- open the master cylinder -- tell us if there is a larger volume between the two reservoirs.... the larger (if there is a difference) needs to serve the FRONT brakes -- and the smaller (if there is a difference) needs to go to the rear. You can simply follow the lines to find if they go to the front or to the back.



++++++++++++++++++++++



Did you BED the brakes after the installation?? Do you know what this means??
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  #10  
Unread 11-30-2017, 01:18 AM
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ok thanks for the help. ill check the vacuum and other stuff this weekend. ill get back to yall.
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