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Lack of vacuum

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Dale:
My 80 model with a 350 has been modified, part of that was a lumpier cam. Works well but it appears to have an issue in reducing the available vacuum.
For example, when I accelerate hard the lights pop up, it is also causing a problem with the heater in that there does not appear to be enough vacuum to open the valve when required.
I saw a video from the states where they installed an auxiliary vacuum pump to fix similar problems created by a big cam, but there were no technical details.
Anyone had  similar issues and found a cure?

bfit:
Sounds fishy to me. sounds like something is not hooked you correctly.
first 
Is there a one way valve in your vacuum  line  from the engine

Bfit

Dale:
Yes there is, I bought a new one and a new filter a while ago as I thought that was the problem but to be honest I am not positive the mechanic has it hooked up properly.
How can you tell?

bfit:
Dale
the guru on this is sirfixalot ( Geoff )
I've seen the headlight going up  when the relay valve  between the headlight  is hosed incorrectly and or hoses are not on  enough to seal

Geoff is bound to see  post in due course
Bfit

sabre:
Hi Dale,
Come across this before but usually only with cam with huge overlap and big bore carb????
Solution is fitting a diesel alternator with vac pump on the rear. I understand the old 2H / 12H Toyota alternator is a popular choice.

I'd check the vacuum with the vac lines removed (and blocked) first. Usually low vacuum will stop lights lifting, not make them lift.
Also agree with Bfit. You should check the hoses and function of the actuator relays for leaks. These die with age.

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