How much vacuum should I have

[GeorgeGerhard]

Hello
I installed a new Holley 750 cfm vac sec last weekend
I hooked up my vacuum gage and noticed at idle in park the gage was a steady 10.
The engine is a 440 with .030 over pistons and a mild camshaft
Is this reading normal?

thank you
George

 

[chasduster]

cam plays a big part in this was this below carb or at the port on the carb.....is your carb dialed in--adjusted correctly..I check them at the maniflod if at all possible and adjust your carb to the highest possible vac at idle...you may see 16

 

[crackedback]

Auto car? What's it pull in gear? What camshaft?

If a 509 that's good to have 10", 256H that's rotten...

Make sure you have the correct initial timing dialed in before worrying about the carb. Correctly set timing makes a world of difference in vacuum and carb adjustments, low end response.