Master cylinder Firewall Hole

[Captainfab]

You know, I don't know of a reason for it other than keeping the master cylinder level, as some stock trucks were higher in the rear. But then if you look at the '67-'72 power brake setups, the master is tilted towards the front. Now the trucks starting in 1988, have the booster bolted directly to the firewall which positions the master basically cylinder level.

I designed my power brake booster brackets with a slight angle upwards simply because it just looks right to me.

Originally Posted by 53lowdown

Sorry to hijack - but why does the Power Booster have to be tilted up like that on these trucks? Is it a clearance problem with the engine or manifolds? The manual master cylinders sit square with the firewall so it can't be a brake rod alignment issue.