First of all, please be easy....I'm no mechanic. I have a '73 vette and installed a cam. I have basically no vacuum in the system and hence my headlights won't accuate. I've been told an external vacuum resovior will likely fix the problem. Can anyone tell me what size/specs I need for the vacuum resovior as well as a little info on installing it?
Thanks a bunch.
Considering there is already a vacuum reservoir in them from 1968 up, I doubt you will have much luck. However, since the reservoir was moved from being a separate tank that sat under the fender near the master cylinder to the big hollow tube that supports the rubber bumper, you may have no tank and have the hollow tube in yours.
Check all of your vacuum lines. Leaks are common, but fixing them makes the system work.
Get a vacuum gauge and read your vacuum. Just how "no vacuum" is "no vacuum". there has to be some for the car to run, but it may be too low to run other things.
Some of the cams made are not good if you plan to continue to drive the car on the street. They have too much valve overlap and thus not enough vacuum to operate things such as headlights, wiper doors, heater/AC controls and distributor advance. On older cars like my '63, the only consideration is vacuum advance which is disconnected and the mechanical is set for 38 degrees total.
If you are going to continue street use buy a small, electric vacuum pump and a small tank. Attach the main vacuum feed from manifold to the tank, except fot the advance line, and all systems should work. Checking the existing lines for cracking and leaks will help things work better.
PDeen
Thanks for the advice. I appreciate it.
JB
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