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Discussion Starter #1
i had another thread for me and my fumbling with a carb and spacer swap, but this problem arose from there. while it was on the car, the Holley 670 Street Avenger wouldnt idle below 1000 RPM. i undid the idle control screw until i think it was almost out completely and still wouldnt drop the idle. holding the throttle arm forward made the idle fall to about 800 RPM but that still would be too much for street driving. i dont think the brakes could hold the car idling that fast. ( well they could but its a real PITA ) any thoughts why it would be idling so damn fast? i really want to use that carb but im not sure i can live with it if its that fast idling. oh yeah.. the choke was off already and it was running for a few minutes so it was plenty warm. it says Street Avenger, so i assumed i could use it on the street ya know? he he. lil help?
 

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Steve

steve,
pretty soon i may contact holley themselves and ask this same exact problem, perhaprs were not the only 2 that have encountered this problem either.Dang thing ideles pretty high at a stoplight.Shouldnt even do that, and at ist if the engine isnt at a full warm up temperature it hesitates alittle n then it runs ok. Iput in nothing but 93 in the car and it runs ok.But when your driving you hear a studdering in the acceleration so i know it may need some timina or perhaps new plugs, but the high idle i goota figure it out also.
thanks
pat
1970 standard triple white convertibble
1970 eliminator MADCATT(turning it into a pro touring car SUICIDE style)
1970 xr7 convertible COMPLETLY rusted out will notify when its in my possesion
 

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Sounds like you have a vacuum leak. Disconnect all vacuum lines, cap them off and see if the idle drops. Fel Pro Print - o - seal intake gaskets are notorious for shrinking over time and causing leaks, a good reason to use Victor Reinz steel reinforced intake gaskets.
 

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Discussion Starter #4
hmmm teh carb that i have on there now runs great though... so i doubt its a leak. unless there is a cap missing on the 670 or something but after i swapped the 670 on and saw how the idle was i put my old 600 back on and its just as it was before. that one idles at 550rpm in gear no problem. im at a loss to explain why, really.
 

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Have you checked the float level? Does it have an automatic choke that is adjusted wrong or broken? You should be able to kill the engine by backing off the idle screw. Now that the carb is off you should be able to turn it upside down and put your lips on a piece of rubber hose attached to the fuel inlet. You can easily tell if the floats are shutting off flow.

Look at the throttle blades. Are they closing all the way or is something interfering?
 

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It might be stuck in fast idle.
poke yer finger dowm here to pop it out of fast idle.

holidsays ya...WOooooooooooooooooooooooohoooooooooo



what
 

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Discussion Starter #7
ill take a look at all of these senarios... it does have the electric choke as well and the floats are something i didnt think of. i tried to knock the fast idle cam down but maybe it was still hung up on something. its all worth a shot.
 

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Discussion Starter #8
oh yeah.. Bowl... i see that you have a rubber plug on the port right by the choke and the secondary lever thingy... i hooked my PCV valve up there... is yours hooked up or did i hooke mine in the wrong spot?
 

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is the secondary butterflies open passed the transfer slot, they might need to be closed abit more to get a good idle. Turn it upside down, and check them. To compensate for a big cam they usually open the sec. 'flies open more to give more idle. Worth a shot to check them.

Rick
 

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Discussion Starter #10
if they are open... how do i close em a bit?
 

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there is a small screw on the underside on the passenger back on the flat spot by the mounting bolt that you unscrew until the plates move. It is a very small screw, and usually require precision screw driver. :)

Rick
 

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. i have all ports plugged but the vac.adv. This street avenger works great, good idle and throttle responce.
I had to adjust the mixture a bit more rich than out of the box setting. i guess its calibrated for a wheezing athsmatic chevy sm blk at the factory.
 
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