A thread for Hydroboost (not Hydravac) questions

[1project2many]

Since people kept jacking my thread about Hydravac to ask about Hydroboost, I decided to be the nice guy and start this for anyone who has Hydroboost questions.

This was the question posted by 57taskforce

I'm wondering since you've got hydroboost expierence, how hard do you think it would be to mount to the fire wall? I've already got a firewall mounted pedal assembly from classic parts. Im currently running 7" dual diaphragm booster. It has hard time stopping 35's. I've got hydroboost on my k2500 and it stops 35's without much issue. So I've been contemplating this swap for a while now. Any insight would be awesome.

I work on Hydroboost systems almost daily. Mounting Hydroboost to the firewall is no more difficult than a vacuum booster. The GM version uses the same holes although in some cases the center hole for the pushrod is a different diameter. The pushrod length may need to be modified and the post on the pedal where the pushrod connects is often at a different location bwhich can alter the pedal pressure required to give stopping power. Because Hydroboost units require a very large amount of pedal pressure if the hydraulic assist is not present, I strongly recommend installing a reinforcing plate on the inside of the firewall.

One consideration is the size of the rotors / drums on your vehicle. Many times the brakes for the 2500 / 3500 vehicle are larger in anticipation of larger loads. While switching to Hydroboost my reduce the pressure needed to stop your vehicle, if the brakes are under size for the application you run the risk of generating enough heat during a fast stop that the brakes fade and lose effectiveness.