VACUUM AT IDLE

What kind of numbers are you guys getting at an idle? Heres my dilemma, no ports on the carb to test it. have 1 port in intake plenum, and I am only getting 5.5-7 at an idle, and it goes up as I crack the throttle.

What rpm do you guys test for to set the power valve

Kasey

i have less than 3" @ idle. power valve selection isn't nearly as critical as some would lead you to believe. it doesn't affect idle mixture at all, only the main circuit. i still run a 65 pv with no problem. more important would be your cruise vacuum. mine is ~15", meaning the power valve is closed (as it should be) at cruise.

I have 15 at 3k, I dont have a power valve, and I am running very fat down the road. Only 8.5 mpg, just checking things out, and I am gonna tune the secondary idle adjustment down cause now I know its rich. Just trying to get this carb figured out.
thanks

If you want better cruising mileage you need a power valve.

Quote:

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If you want better cruising mileage you need a power valve.

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correct. get a power valve in that thing! oh, and don't forget to jet down on the primary side (assuming you'll have a power valve on primary only). 8 numbers down should do it.