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johnmyster · 08-27-2008, 08:01 PM

Well,

My memory is rusty, but I think vacuum boosters work because they have vacuum on BOTH sides of the diaphram. Then, when you push the pedal, you allow atmospheric pressure to push against the back side. The harder you push, the harder you spring-load the inlet regulator, and the more pressure the side facing you gains. That's the "squshing" sound made when you tap the pedal - air rushing in on your side.

Maybe you could more easily have power assist by using compressed air. Think about it. The vacuum system works with less than 15 PSI of differential. With a few old freeon tanks at 120 psi, you could probably do quite a bit of braking if you only needed 10 or 15 psi of pressure on your side. You'd recharge on air at the same time you recharged your batteries.

You'd be a ground breaker if you figured out how to do this. The booster system itself is pretty simple. If I had junkyard resources, I'd start tinkering with one myself.

I'm just thinking that an electric pump is going to be a bad way to spend your watts. And if you had to do it on-board, it'd be better to have a compressed air pump than a vacuum pump.

They guy on here with the beetle could even use compressed air from his spare tire - an old VW joke...

08-27-2008, 08:01 PM	#486 (permalink)
johnmyster EcoModding Lurker Join Date: Aug 2008 Location: Virginia Posts: 87 Brown Bus - '98 GMC Sonoma X-Cab SLS 90 day: 31.37 mpg (US) Thanks: 0 Thanked 2 Times in 2 Posts	Well, My memory is rusty, but I think vacuum boosters work because they have vacuum on BOTH sides of the diaphram. Then, when you push the pedal, you allow atmospheric pressure to push against the back side. The harder you push, the harder you spring-load the inlet regulator, and the more pressure the side facing you gains. That's the "squshing" sound made when you tap the pedal - air rushing in on your side. Maybe you could more easily have power assist by using compressed air. Think about it. The vacuum system works with less than 15 PSI of differential. With a few old freeon tanks at 120 psi, you could probably do quite a bit of braking if you only needed 10 or 15 psi of pressure on your side. You'd recharge on air at the same time you recharged your batteries. You'd be a ground breaker if you figured out how to do this. The booster system itself is pretty simple. If I had junkyard resources, I'd start tinkering with one myself. I'm just thinking that an electric pump is going to be a bad way to spend your watts. And if you had to do it on-board, it'd be better to have a compressed air pump than a vacuum pump. They guy on here with the beetle could even use compressed air from his spare tire - an old VW joke... __________________ Meh Truck Last edited by johnmyster; 08-27-2008 at 08:07 PM..