Brake pedal ratio

Shocks, Springs, Brakes, Frame, Body Work, etc

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lada ok
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Re: Brake pedal ratio

Post by lada ok » Tue Jan 27, 2015 1:52 pm

If it's for a FOOT brake, a hole in the floor will suffice, ...stopping power is relative to co efficient of friction material

pdq67
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Re: Brake pedal ratio

Post by pdq67 » Fri Jan 30, 2015 3:02 am

I think, now I think that most vehicles brake pedals have two holes in them.

A top hole for non power and a bottom hole for power. Look close and I figure that you will see where we can install a booster setup for the lower hole on the firewall and no booster up top for the top hole. The firewalls should have the needed extra studs already in place for a booster if not mistaken.

Find a vehicle that is sized/weighted like you want to use and measure away imho...

I have a really old mag that said to use a 1.25" diameter master cylinder for a four wheel disc, "cheap big brake" setup like I now have on my car because of the large capacity 1969 and Van 2-15/16" dia. big single piston front calipers and the something like 2-3/8" dia. 1980 e-brake Cad Seville rear calipers. Worse thing that can happen is that I may have to use a smaller bore M/C if my pedal pressure is too high?

FWIW, I have another old mag that lists all of GM's front and rear disc brake sizes and vehicles and years used on info....

I created a front caliper template that mounts the 2-15/16" caliper on a 1988 13" 'Vette front rotor and have given copies of it away to a bunch of guys through the years. Do a search on both T/C's for pdq67's CBB front and rear install if you want. It might be under pdqCBB???

My rear rotor on my 12-bolt rear end is a 1989 Camaro 12" dia. rear one... Custom caliper bracket for it too....

pdq67

BigBlocksOnTop2
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Re: Brake pedal ratio

Post by BigBlocksOnTop2 » Fri Jan 30, 2015 7:01 am

pdq67, a smaller bore m/c will increase pressure and takes a longer pedal push.

Brian P
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Re: Brake pedal ratio

Post by Brian P » Fri Jan 30, 2015 10:48 pm

Most car brake pedals now only have one possible connection to the master cylinder, because they're all power assisted, and there is not even any provision made at all for a non-power-assisted-brake version.

cjperformance
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Re: Brake pedal ratio

Post by cjperformance » Fri Jan 30, 2015 11:21 pm

Brian P wrote:Most car brake pedals now only have one possible connection to the master cylinder, because they're all power assisted, and there is not even any provision made at all for a non-power-assisted-brake version.
What! - i thought the current mustang was still stock with 4 wheel drums!! :lol:
Craig.

pdq67
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Re: Brake pedal ratio

Post by pdq67 » Sun Feb 01, 2015 12:30 pm

I'm sorry guys, I'm thinking our old pony and muscle cars, (and older), here.

Please carry-on.

pdq67

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Re: Brake pedal ratio

Post by Warpspeed » Sun Feb 01, 2015 3:10 pm

Quite a few of us here are into "old iron".
Hot rods, muscle cars, that kind of stuff.
Cheers, Tony.

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