70 LS1

Since the power brakes and headlights, and wiper door work off of a vacuum, what happens when you add a turbo or supercharger and now have a positive pressure in the intake?

Do you have to do something special to get it all to work?

lowflyer

How about a Vac pump?

jamesx0

Can't you just use the intake side of the turbo/supercharger as your vacuum source?

Turbo-Jet

The signal source is (re)located upstream of the compressor.

Twin_Turbo

Everything will work fine if you have the check valves in good working order. It's not like you're under boost all the time so you will have vac from the manifold most of the time, and I don't see anyone tryibg to open the headlights under boost or apply the brakes with the engine screaming :)

groovyjay

:rofl: :lolg: :lol:

And if you someone wants to do it, I'd suggest electric head light conversion hydraboost. :yesnod:

norvalwilhelm

I agree with Twin_Turbo. You only have boost under hard throttle applications. Normally cruising down the road I have about 9 inches of vacuum in the intake manifold and about twice that above directly under the carb. I could use either source for vacuum. Other then setting the line lock you do not apply the brakes and the throttle at the same time.

Monty

I have the factory checkvalve in the headlight and HVAC vacuum port connection and those systems are unaffected by manifold pressure. My engine pulls about 11-12" of vacuum at idle, and a little less than that at low-load crusing rpms. As mentioned, it's usually not a problem for the brakes either, because you've typically closed the throttle when you apply the brakes, and vacuum would be present in the manifold at that point. The only problem I had was if I attempted to flash the convertor and spool up the turbos with the brake applied (powerbraking), I would lose vacuum brake assist, requiring alot of leg effort to hold the brakes. Obviously, this is an uncommon situation, but it's the main reason I went with the Hydraboost.


[Modified by Monty, 2:08 PM 2/3/2003]

70 LS1

Thanks guys. I am toying with the idea of twin turboing the LS1.

Monty

[Modified by Monty, 9:41 AM 2/4/2003]