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Discussion Starter #1
Hello everyone, first time posting in the forum, hopefully you have some suggestions for me.
Took the rolling chassis out for the first drive last weekend, and it ran pretty darn good overall! I am a bit concerned about the stopping ability considering the weight and how much braking is on the car.
Here is how the car is set up
1995 5.0
stock 5.0 master cylinder
stock proportioning valve
donor had power brakes and abs, the new car does not
stock single piston front calipers and rotors, and new pads
FFR 11.65 rear brakes with the new pads they include
brake pedal modification as per the instructions
brake pedal is nice and firm, just can't lock up any of the brakes
Any ideas are welcomed, I'm suspecting the proportioning valve may be a great place to start

Ken in Glendale , Ca
 

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Pro FFR Builder and Moderator
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You need to change the master to a smaller bore size such as 7/8" or 15/16" and you need to delete the factory proportioning valve. That will go a long way to making your brakes better.
 

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FFCobra Craftsman
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Also look at better pads. I happened to start w/ Hawk brand while others use EBC or Carbotech. In the Hawk line the HPS will have much more grip for a given amount of pedal effort than stock pads you have now. The HP+ are even better but they do dust a lot more.RE: the prop valve, you can get rid of it by replacing it w/ unions. If you have the one brake lines that is larger diameter (Left Front IIRC) it could be easier to leave the valve but gut it.

You replace the cap w/ a solid cap that can be ordered from Ford.
 

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You need to change the master to a smaller bore size such as 7/8" or 15/16" and you need to delete the factory proportioning valve. That will go a long way to making your brakes better.
Bingo. Had same exact problem. For casual driving the brakes were OK. Hard or panic stop and they were dangerous. Took to a sports car racer in town. He checked out the complete system and found no problems. Then he concentrated on master cylinder. Replaced with smaller bore cylinder and BAM. Brakes now work fine. Bigger is not always better.
 

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Official OLD GUY
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X2

What Gordon said - factory master cylinder is "sized" for power assist . . . and you stated that you don't have that now.

X2 on "gutting" the proportioning valve too . . . it's designed for rear drums (originally) and you've upgraded to bigger disks.

Doc :beerchug:
 

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Lay posi
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You can put the 95 power brake booster on. I used a 94 booster, it works great. I used Whitby's frame adapter. With the brake booster, you can leave everything else as is (even the stock proportioning valve) and you will have excellet street car brakes. I did have to lengthen the steering shaft on a MKIII so the universal joint would clear the booster though.

Wibby
 

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You are much better off to remove the factory prop valve than to gut it. If you empty it out you lose the safety of one set of brakes working if the other side fails.

Aggressive brake pads really will make a big difference, we will run more of the race compound than just the high perfomance street compounds, so a Hawk DTC60 instead of an HPS. Also the master cylinder size should be 15/16 for good leverage, but a lot of the parts stores will swap out masters for bigger ones to consolidate part numbers so whatever one you buy double check it before you install.
 

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Too Cheap to paint!
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Used the 15/16 bore MC from the 94 Cobra (4 wheel disc) with no prop valve on mine with all discs. Use the Hawk pads, used grabbier pads in back to provide mechanical brake bias. I have manual brakes, so did the pedal mod.

Once brakes are warm, stops damn quick with a firm push.
 

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Discussion Starter #12
Thanks for the replies

Thanks everyone, sounds like we have a consensus on replacing the master cylinder, and removing the proportioning valve. I'll try the different pads as well after the initial test drive and see where we're at.
Thanks to all,

Ken in Glendale Ca.
 

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Discussion Starter #14
Jim is the bore size stamped on the master cylinder somewhere so I can be sure?

Thanks,
Ken
 

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On some master cylinders you will find the size but not many of the newer ones. I think they start with the same casting and just bore out the size they want so they can't cast the number into the part. If you don't have a caliper you can use a quarter as an estimate, it is just a hair under 15/16. If it fits sloppy then the bore is to big. (easy to do at the parts store too)
 

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