Brake Pedal Motion Ratio

[Diamond Level Motorsports]

Lets assume that I am using 3/4" master cylinders for both the front and rear of my FV. Does anyone have an approximate pedal motion ratio?

I am thinking somewhere between 4:1 and 6:1

[HayesCages]

We've always used 5/8" front and 3/4" rear masters. Wouldn't the ratio depend upon where the pushrod pivot is located in relation to the lower pivot on the pedal as well?

[Diamond Level Motorsports]

We've always used 5/8" front and 3/4" rear masters. Wouldn't the ratio depend upon where the pushrod pivot is located in relation to the lower pivot on the pedal as well?

Yes, that is exactly the information I am looking for. The ratio between the pedal pivot, master cylinder drive rod, and the end of the pedal where the foot pressure is applied.

[HayesCages]

I think the last pedal we made was 2.5" from lower pivot to pushrod pivot and about 9" tall over-all.

[TJSFVGUY]

The Tilton website has drawings of the pedals, cylinder mounts, etc. Lots of good info there.

[jpetillo]

My cars have brake elver ratios of 2.45 and 3.0, and other people's fees I've asked have as high as 3.5. I have the 3/4" rear & 5/8" front master cylinder combo.

[Daryl DeArman]

Lets assume that I am using 3/4" master cylinders for both the front and rear of my FV. Does anyone have an approximate pedal motion ratio?

I am thinking somewhere between 4:1 and 6:1

As long as you can get in the foot box and m/c mounts you are working with. Are you starting with a clean slate?

My FV originally had this horrible brake pedal assembly that somebody grafted additional height on the pedal and it was still less than 3:1. I couldn't lock those tires up if I tried. I bought a Willwood 6:1 floor mount pedal and had to cut a bit over 1" off the pedal height, to get it to fit in the footbox. That ended up giving me about 5.29:1 and while a huge improvement....I still felt like I could tolerate more travel/leverage/modulation.

[Diamond Level Motorsports]

As long as you can get in the foot box and m/c mounts you are working with. Are you starting with a clean slate?

My FV originally had this horrible brake pedal assembly that somebody grafted additional height on the pedal and it was still less than 3:1. I couldn't lock those tires up if I tried. I bought a Willwood 6:1 floor mount pedal and had to cut a bit over 1" off the pedal height, to get it to fit in the footbox. That ended up giving me about 5.29:1 and while a huge improvement....I still felt like I could tolerate more travel/leverage/modulation.

Daryl, do you remember what size master cylinders you had with this set up?