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Rev · 01-21-2001, 07:21 PM

I hate to disagree here, but the main jets are part of the main metering circuit and not part of the idle circuit in Holley carbs. Rich idle can be caused by a leaking needle & seat on the pimary or secondary side. If you look into the secondaries, a drip into the secondary bores can be seen if the inlet valve is allowing the secondary bowl to overfill. The same applies to the primary side. A leaking power valve on the primary side will allow extra fuel to drip in from the main metering orifice on the primary side. Changing the main jets won't help either of these problems or affect the idle in any way. Look for other ways that extra fuel is coming in. My $.02.

Rev

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'66 Coupe, 306, 300 HP, C-4, 13.97 e.t., 100.3 mph
1/4 mi.

01-21-2001, 07:21 PM	#8
Rev Registered Member Join Date: Nov 1998 Location: Houston, Tx. Posts: 3,887	I hate to disagree here, but the main jets are part of the main metering circuit and not part of the idle circuit in Holley carbs. Rich idle can be caused by a leaking needle & seat on the pimary or secondary side. If you look into the secondaries, a drip into the secondary bores can be seen if the inlet valve is allowing the secondary bowl to overfill. The same applies to the primary side. A leaking power valve on the primary side will allow extra fuel to drip in from the main metering orifice on the primary side. Changing the main jets won't help either of these problems or affect the idle in any way. Look for other ways that extra fuel is coming in. My $.02. Rev ------------------ '66 Coupe, 306, 300 HP, C-4, 13.97 e.t., 100.3 mph 1/4 mi.