RPM's drop.
Thread Starter
Senior Member since 1492
Joined: Aug 2000
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
RPM's drop.
After I put in the clutch, coming to a stop, say from 40MPH & 2500rpm, the tach goes well below the idle speed(850) but returns to idle speed in about 1 second.
It'll drop down to about 650-700 and then return to 850???
It'll drop down to about 650-700 and then return to 850???
Melting Slicks
Joined: Nov 2003
Posts: 2,362
Likes: 1
From: San Antonio TX
Check your float bowl settings. 
I will add a bit more lol. Your float leval maybe too low thus uncovering the jets and causing a slight lean condition till the fuel comes back up. Take out the Float bowl plugs and as the engine runs it should just barely dribble out of the float bowl hole.
I will add a bit more lol. Your float leval maybe too low thus uncovering the jets and causing a slight lean condition till the fuel comes back up. Take out the Float bowl plugs and as the engine runs it should just barely dribble out of the float bowl hole.
Last edited by SHAKERATTLEROLL; Oct 17, 2004 at 08:03 PM.
Race Director
Joined: May 2004
Posts: 11,920
Likes: 2
What about the idle circuit?
As the butterflies close, there is more back pressure!
Shouldn't opening the idle screws 1/8 turn or so on the primary side keep the RPM's at 900 or so??....a bit of air=a bit of idle circuit flow...??
coming to a stop, say from 40MPH & 2500rpm
Shouldn't opening the idle screws 1/8 turn or so on the primary side keep the RPM's at 900 or so??....a bit of air=a bit of idle circuit flow...??
Thread Starter
Senior Member since 1492
Joined: Aug 2000
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
Idle circuit??? I'm a Holley neophyte.
I set the floats about 500 miles ago when this carb was on my SB.
I'm gonna switch carbs tomorrow. I have a new 830DP waiting to go.
I set the floats about 500 miles ago when this carb was on my SB.
I'm gonna switch carbs tomorrow. I have a new 830DP waiting to go.
Race Director
Joined: Sep 2004
Posts: 11,874
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Originally Posted by Jughead
After I put in the clutch, coming to a stop, say from 40MPH & 2500rpm, the tach goes well below the idle speed(850) but returns to idle speed in about 1 second.
It'll drop down to about 650-700 and then return to 850???
It'll drop down to about 650-700 and then return to 850???
what about needle bounce? is this a cable driven tach? can you definitely hear the engine surge from the 650 to the 800 rpm range to rule this out?
Thread Starter
Senior Member since 1492
Joined: Aug 2000
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
Originally Posted by bobs77vet
what about needle bounce? is this a cable driven tach? can you definitely hear the engine surge from the 650 to the 800 rpm range to rule this out?
Thread Starter
Senior Member since 1492
Joined: Aug 2000
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
Originally Posted by 79VetteMike
Have you considered a vacuum leak?
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From: Forked River NJ
My Holley does the same thing. I talked to my brother in law and his does the same thing. I think it is caused from fuel slosh in the fuel bowls. I have adjsuted my fuel level a couple of times and it is better now but if I really hammer the brakes it still slows down a little. The more miles I put on it the better it seems to get also.
