Conversions & Hybrids - Do I Need a Vacuum Reservoir?

I'm installing a Hot Rod Air AC unit that has some vacuum operated controls. Is it necessary to install a vacuum reservoir for suitable operation of the controls (heater and defrost doors)? If so, can anyone advise a source for a nice compact unit with valve? Doesn't need to be a polished cannister, etc since it will be out of sight; a auto specific application perhaps?

Only down side to not using one would be inadequate operation in low engine vacuum situations like climbing a hill or on accelleration.
Thanks,

Andy1

It would be a good Idea.. as many cars have at lease a small one to help assist the Vacuum operated controls.

My Chevelle has a small canister that is shaped in the size of a softball. It is small enough to be either hinden in the fender well or evey bring it inside the firewall under the dash or kick panel. One of these days, I will move it.

http://i190.photobucket.com/albums/z296/BajaCruz-in/misc/vaccumcanister.jpg

in the picture, you can see it between the air cleaner and HVAC box. Has just a In and a valved out port.

What car is this for ?

bczee,

Is that a stock Chevelle reservoir? What year application? Is the valve integral to the reservoir, or separate? I was thinking of using the brake booster port of the back of the intake a a source of vacuum since I don't have power brakes.

My swap is a 914 Porsche

Andy1

Mine is a stock oem canister for a 71 Chevelle. I have it connected to the back of the intake, not the Brake pot but the port opposite of the Brake booster port. The MAP is in between the two port.

As far as the Valve, I am not sure if there is one, but if there is, it inside of it. I've just never checked out this part of the system.

Manuy GM cars of the 60's and 70's had something like these canisters.

914.. cool.. there are two 914 with SBC's running around here.

[QUOTE=Andy1;9713392]I'm installing a Hot Rod Air AC unit that has some vacuum operated controls. Is it necessary to install a vacuum reservoir for suitable operation of the controls (heater and defrost doors)? If so, can anyone advise a source for a nice compact unit with valve? Doesn't need to be a polished cannister, etc since it will be out of sight; a auto specific application perhaps?

Only down side to not using one would be inadequate operation in low engine vacuum situations like climbing a hill or on accelleration.
Thanks,

Make sure you install a one way valve between your vacum source and the resevoir to keep the vacum from bleeding off when you shut off the engine.
Alan

Round thingies don't lend themselves well to tight spaces, but I should be able to find space for a "softball." If the check valve is not integral to the reservoir, then I suppose I can always fab a cylindrical shaped reservoir; it's just easier to buy something.

Alan, where can I buy the check valve and/or what vehicle application would it be found in?

Thanks guys,

Andy1