POWERBRAKEBOB
Banned
- Joined
- Mar 28, 2005
- Messages
- 318
Hydroboost Conversion
It's true. Vacuum boosters need vacuum to work. 20" of vacuum is where they rate the power outout. My point is that high vacuum is hard to acheive with a 231ci motor, turbocharged, and in overdrive. Everybody points to the TTA, but the powermaster was out of production in 1987, and G.M. did not want to go back to that. They put in a second check valve to prevent manifold pressure from going up against the vacuum booster. Obviously, air Pressure is the opposite of vacuum. How can a vacuum booster work under air pressure? Air pressure inside that booster will blow it apart. Try sticking a shop blow gun into a vacuum booster. Not good. The master cyl and can will be laying loose somewhere in the engine compartment. Does anyone know if the camshaft for the G.N. and the TTA are the same? The factories have always had to grind the cam specs to allow the engine vacuum to operate the brakes. Otherwise they could sell an engine with a much higher output. The Cranes and Comp cams people would not need to exist. When those aftermarket cam companies sell a cam, they ask if it will be for the street, and caution customers to be conservative on duration, for vacuum reasons. With the H/B, you can run any camshaft you can live with. A long duration cam in a TTA would deplete any vacuum to operate the booster. Would a hydroboost increase the stopping power of a stock TTA? Absolutely, and we have done it.
It's true. Vacuum boosters need vacuum to work. 20" of vacuum is where they rate the power outout. My point is that high vacuum is hard to acheive with a 231ci motor, turbocharged, and in overdrive. Everybody points to the TTA, but the powermaster was out of production in 1987, and G.M. did not want to go back to that. They put in a second check valve to prevent manifold pressure from going up against the vacuum booster. Obviously, air Pressure is the opposite of vacuum. How can a vacuum booster work under air pressure? Air pressure inside that booster will blow it apart. Try sticking a shop blow gun into a vacuum booster. Not good. The master cyl and can will be laying loose somewhere in the engine compartment. Does anyone know if the camshaft for the G.N. and the TTA are the same? The factories have always had to grind the cam specs to allow the engine vacuum to operate the brakes. Otherwise they could sell an engine with a much higher output. The Cranes and Comp cams people would not need to exist. When those aftermarket cam companies sell a cam, they ask if it will be for the street, and caution customers to be conservative on duration, for vacuum reasons. With the H/B, you can run any camshaft you can live with. A long duration cam in a TTA would deplete any vacuum to operate the booster. Would a hydroboost increase the stopping power of a stock TTA? Absolutely, and we have done it.
