well put in new autometer vacuum guage in car. notice that when under load stepping on throttle the vacuum goes to 0... and then comes up when I let off, is this normal, might be a stupid question, just seems weird. when in park and I rev it up the hg's. go up. but under load goes straight to zero quick?

 

It is working correctly. WOT is low vacuum, idle and cruise is high vacuum.

You've never worked with carb's have ya

 

Its normal, dont worry about it. Think about it for a second, when the throttle is closed and the engine is idling, there will be high vacuum in the intake. When the throttle opens, vacuum drops since it is exposed to atmospheric pressure.
Kind of like when you suck on a straw and you put your finger at the end, and when you take it off, air rushes in filling the vacuum with atmosphere, same concept.

 

damn I feel dumb...

yeah not much experience with carbs either..

see that learn something everyday....

 

Think about it this way, with your foot off the gas you not feeding the intake any air (ignoring the idle air control) and the pistons are still sucking air creating a strong vacuum. When you put your foot on the gas (open the throttle body), you're now letting outside air into the intake dropping the vacuum.