Brake pedal ratio
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Brake pedal ratio
Can someone advise me on the correct pedal to master cylinder ratio for a car WITHOUT power brakes?
Thanks so much
Jim
Thanks so much
Jim
Re: Brake pedal ratio
Thanks, MiniV8, but that's not quite what I was looking for. There is a recommended ratio of something like 5 or 6 to one, as I recall. Just trying to get the right one
Thanks again
Jim
Thanks again
Jim
Re: Brake pedal ratio
I just measured a 1964 Falcon and brake cylinder post is 2" down from pivot and center of foot pedal pad is 12" so 6 to 1 I guess.
On my '64 Ranchero with single master cylinder I installed the power brake dual master cylinder from a '71 Cougar along with the disc brakes from it but not the power brake booster. The pedal was harder to push but not Too hard for me. The original Falcon size is 7/8" or 15/16" I think and the Cougar is 1" or 1-1/16" so larger is why pedal pressure was up as I expected to be.
On my '64 Ranchero with single master cylinder I installed the power brake dual master cylinder from a '71 Cougar along with the disc brakes from it but not the power brake booster. The pedal was harder to push but not Too hard for me. The original Falcon size is 7/8" or 15/16" I think and the Cougar is 1" or 1-1/16" so larger is why pedal pressure was up as I expected to be.
Dale C.
Re: Brake pedal ratio
6 t0 1 but 7 to 1 is better...
I run 6 to 1 with a power brake booster because my motor only makes 10" at idle.. It works...
I run 6 to 1 with a power brake booster because my motor only makes 10" at idle.. It works...
Re: Brake pedal ratio
If you can't get the ratio you desire you can always use a little smaller master cyl bore which will increase the pressure and provide more
stopping power.
We do this all the time on circle track cars to get the front to rear pressure balance that we need.
Gov
stopping power.
We do this all the time on circle track cars to get the front to rear pressure balance that we need.
Gov
a passion for racing
Re: Brake pedal ratio
Pedal ratio really has more to do with stroke at the end of the pedal than anything else.
You want to be able to stroke the master cylinder over its full range of travel, and end up with about maybe six to seven inches of pedal travel to the floor.
Much less travel than that and pedal effort increases, much more travel, and the brake pedal will end up being so high off the floor, it just won't feel right. If you are tall, with long legs, a bit of extra travel may not feel quite so bad.
The actual pedal ratio depends on the master cylinder stroke, and that can vary a bit with design, but is often around one inch.
So your actual pedal ratio might end up in the range of something like 5:1 to 7:1
You want to be able to stroke the master cylinder over its full range of travel, and end up with about maybe six to seven inches of pedal travel to the floor.
Much less travel than that and pedal effort increases, much more travel, and the brake pedal will end up being so high off the floor, it just won't feel right. If you are tall, with long legs, a bit of extra travel may not feel quite so bad.
The actual pedal ratio depends on the master cylinder stroke, and that can vary a bit with design, but is often around one inch.
So your actual pedal ratio might end up in the range of something like 5:1 to 7:1
Cheers, Tony.
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Re: Brake pedal ratio
That is a point you need to take and can be done with an empty master......Warpspeed wrote:Pedal ratio really has more to do with stroke at the end of the pedal than anything else.
You want to be able to stroke the master cylinder over its full range of travel, and end up with about maybe six to seven inches of pedal travel to the floor.
Much less travel than that and pedal effort increases, much more travel, and the brake pedal will end up being so high off the floor, it just won't feel right. If you are tall, with long legs, a bit of extra travel may not feel quite so bad.
The actual pedal ratio depends on the master cylinder stroke, and that can vary a bit with design, but is often around one inch.
So your actual pedal ratio might end up in the range of something like 5:1 to 7:1
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Adam
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Re: Brake pedal ratio
What car, what brakes & what use?Kahuna wrote:Can someone advise me on the correct pedal to master cylinder ratio for a car WITHOUT power brakes?
Thanks so much
Jim
Craig.
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Re: Brake pedal ratio
No kits.... Forget car,brakes and all..cjperformance wrote:What car, what brakes & what use?Kahuna wrote:Can someone advise me on the correct pedal to master cylinder ratio for a car WITHOUT power brakes?
Thanks so much
Jim
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Adam
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Re: Brake pedal ratio
Not as far as I know..... If he needs help I am within 30 miles.cjperformance wrote:af2 , has this project/op's question been scrapped?
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Adam
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