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Author Topic: Is there a minimum throttle opening requirement?  (Read 2915 times)

Offline Shark Racer

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Is there a minimum throttle opening requirement?
« on: January 29, 2013, 09:34:09 AM »
Right now, I can get a smooth idle speed(675rpm or so) with the idle speed screw barely touching the primary throttle stop.

Will this have any effect on transition fuel?
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Offline Cliff Ruggles

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Re: Is there a minimum throttle opening requirement?
« Reply #1 on: January 30, 2013, 04:57:11 AM »
As throttle angle increases, fuel continues to flow from the mixture screw holes, and then from the transition slots as the main system comes on line.  This happens at a very low throttle opening, due to the efficiency of the boosters.  It should be fine provided the main system is adding enough fuel.  It will let you know if it isn't....Cliff
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Offline nut

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Re: Is there a minimum throttle opening requirement?
« Reply #2 on: February 09, 2013, 03:34:03 PM »
 Didnt know where to start but this just as well. Stubbled across your site with some ? on a quad. Ive been workin on a 73 Stingray that someone has put in a 1976 305 with the small cc heads. Still stock stuff but replaced the chain,valve seals,points plugs and coil. Dwell @ 30 deg with the timing @ 8. Starts like a champ and very crisp BUT, just off idle itll want to stumble through the rpm,s. Ive pulled the carb and changed the base gasket and the mix screws do adj. Only thing Inotice is the plates are shut tigh with the idle screw backed off completly. Any thoughts or sugg.? Will a base gasket change much from open to closed design? Any help much needed! ???
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Offline Cliff Ruggles

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Re: Is there a minimum throttle opening requirement?
« Reply #3 on: February 10, 2013, 04:56:26 AM »
What is the carburetor number?....Cliff
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Offline nut

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Re: Is there a minimum throttle opening requirement?
« Reply #4 on: February 10, 2013, 06:22:57 AM »
Will get them. I think its a 4mv.  750cfm
305 never had a 4 on it. The chokes a heat riser coil but has an egr on the intake so I think they are off a 1975 350.
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Offline nut

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Re: Is there a minimum throttle opening requirement?
« Reply #5 on: February 10, 2013, 06:35:14 AM »
Quote from: nut on February 10, 2013, 06:22:57 AM
Will get them. I think its a 4mv.  750cfm
305 never had a 4 on it. The chokes a heat riser coil but has an egr on the intake so I think they are off a 1975 350. From what I gather the pri. jets are plugged/gummed up from sitting? Shouldnt it act the same cold on high idle? Almost as if it had an intermittied miss intill you hit the gas.(juice it)
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Offline nut

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Re: Is there a minimum throttle opening requirement?
« Reply #6 on: February 10, 2013, 09:30:50 AM »
Worked on the choke 2 day(rich) and balanced the mix screws. Carb #er is 7403202fs. My book says 73 but not off a vette. Half my vac lines are plugged that it had some emissions/extras that arent equipt on this car. Good thing it is clearing up.(Less freq.) Added a 1/2 bottle of dragon power with some good gas but tough to pin down. Anything you could help me on with the numbers Cliff would be helpful! Thank You!
     Oh ya! Sorry for takin you thread Racer!
« Last Edit: February 10, 2013, 09:34:48 AM by nut »
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Offline Shark Racer

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Re: Is there a minimum throttle opening requirement?
« Reply #7 on: February 10, 2013, 12:01:08 PM »
No problem.... :) all info is good info.
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