Brake Booster question

[vetracer]

I have a 2011 mustang GT that came with the 2 piston Brembo Performance Package front brakes. I've upgraded the brakes to the 15" front and 13.8" rotor GT500 set up using 2018 Bullitt 6 piston Brembo's up front. Due to the larger piston area of the 6 piston Brembo's I have a longer pedal travel than I'd like. I still have the stock 2011 GT brake booster, P/N BR3V-2B195 -AA. I'm looking at upgrading to the 2012 Boss 302 brake booster P/N DR3Z-2005-A. My problem is when researching the Boss 302 booster I can't figure out if it stiffens the pedal and reduces pedal travel. Different vendors tell different stories. One says it reduces pedal effort 30% implying a larger diameter diaphram, which is not what I want. Others say it reduces boost by 30%. I want to decrease boot assist and reduce pedal travel. Can someone clarify whether the Boss 302 booster reduces pedal travel by reducing boost assist by 30%. TIA
Larry

 

[vetracer]

I found this bit of information on the Mustang Forum which I found most interesting as I think it addresses some of the brake travel issues I am trying to resolve.

“There is also a rubber disk in between the booster diaphram/input rod and MC rod (output). I suspect Ford put it in for NVH, but no one has ever explained to me why it is there and why I should not replace it with something harder, maybe even Delrin to get some better pedal feel. It fits in the inner end of booster rod, see here. Many go to great lengths to stiffen MC and/or firewall to eliminate flex, yet Ford puts a "squishy" rubber disk in your stock braking system from the get go, go figure!! I have done a ton of modified/upgraded braking systems on old Ford trucks and Broncos with different boosters/MC's and even several different style hydro-boosts, and have never seen a rubber disk like this before.”

I was surprised to see in this post that there is a .312" rubber washer between the booster rod and the MC rod. The compression of that washer multiplied by the pedal ratio would explain much of the extra travel when the power boost is applied. I'm going to take apart a booster and see if this washer can be easily replaced with one made of Delrin.

 

[PatientZero]

Interesting

 

[xr7]

I found this bit of information on the Mustang Forum which I found most interesting as I think it addresses some of the brake travel issues I am trying to resolve.

“There is also a rubber disk in between the booster diaphram/input rod and MC rod (output). I suspect Ford put it in for NVH, but no one has ever explained to me why it is there and why I should not replace it with something harder, maybe even Delrin to get some better pedal feel. It fits in the inner end of booster rod, see here. Many go to great lengths to stiffen MC and/or firewall to eliminate flex, yet Ford puts a "squishy" rubber disk in your stock braking system from the get go, go figure!! I have done a ton of modified/upgraded braking systems on old Ford trucks and Broncos with different boosters/MC's and even several different style hydro-boosts, and have never seen a rubber disk like this before.”

I was surprised to see in this post that there is a .312" rubber washer between the booster rod and the MC rod. The compression of that washer multiplied by the pedal ratio would explain much of the extra travel when the power boost is applied. I'm going to take apart a booster and see if this washer can be easily replaced with one made of Delrin.

View attachment 86069

View attachment 86070

Getting rid of a squishy rubber part would be great NVH be damned! Will be waiting to see the results.