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Discussion Starter #2
> My 73 came with the Holley 4Bbl conversion
> by CarTech. Problem is setting idle. Anybody
> have the same.

I've worked on carbs most of 24 years, One reason I stay away from the Fuel injected Z's, I've never seen any 4bbl conversion to a Z that worked worth a damm and sure don't recomend holley's on a Z. They seem to like to backfire and blow out the Power valves when cold. There is a fix for the Holley and I'd really recomend it for a Z car. You can get it from the JEG'S Magazine(www.jegs.com).The manifolds are terrible. I'd run a Carter carb. Seen better results with those carbs on Z's. About the best way to adjust it is to get a vacume gauge or the Manometer tool and a color tune tool (it's sensitive enough to get a good mixture in the idle circuit) and make sure the idle mixture screw's are both even, all you can do is start around 1.5 turns out and go from there. Get the best low idle setting you can get and adjust the main idle for idle speed. Make sure the vacume doesn't show any gasket leaks or valve trouble or nothing you do with the carb will help. I hope you have the conversion that adapts to the orig. SU carb. manifold, it flows more evenly to all cyl.. The other type that bolts to the head doesn't flow evenly and you'll never get a good running car, It also has way to much surface area and it condenses the gas to fast to flow right. I'd scrap/sell it and get dual webbers. You'll be a lot better off all the way around. Good luck anyway and get the vacume gauge and go from there. One thing also, if you don't like the carb that much check out the JEG'S site, they sell some very good carbs and some are better for the Z than a average store bought Holley.
 

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Discussion Starter #3
Re: Correction on adjustment

Sorry, I was thinking of the end result and not how to get there. After setting the idle mixture screws to a even amount of turns, set the rpm pretty low, adjust the mixture screws till you get the highest idle out of them but keep it under 800rpm if you can while making the adjustments, get the highest stable RPM out of the adjustment and then set the final adjustment with the main idle adjuster to end up with a low stable idle. I kept seeing this Z car after flames from a backfire with a 4bbl and got distracted... :)

I've worked on carbs most of 24 years, One
> reason I stay away from the Fuel injected
> Z's, I've never seen any 4bbl conversion to
> a Z that worked worth a damm and sure don't
> recomend holley's on a Z. They seem to like
> to backfire and blow out the Power valves
> when cold. There is a fix for the Holley and
> I'd really recomend it for a Z car. You can
> get it from the JEG'S
> Magazine(www.jegs.com).The manifolds are
> terrible. I'd run a Carter carb. Seen better
> results with those carbs on Z's. About the
> best way to adjust it is to get a vacume
> gauge or the Manometer tool and a color tune
> tool (it's sensitive enough to get a good
> mixture in the idle circuit) and make sure
> the idle mixture screw's are both even, all
> you can do is start around 1.5 turns out and
> go from there. Get the best low idle setting
> you can get and adjust the main idle for
> idle speed. Make sure the vacume doesn't
> show any gasket leaks or valve trouble or
> nothing you do with the carb will help. I
> hope you have the conversion that adapts to
> the orig. SU carb. manifold, it flows more
> evenly to all cyl.. The other type that
> bolts to the head doesn't flow evenly and
> you'll never get a good running car, It also
> has way to much surface area and it
> condenses the gas to fast to flow right. I'd
> scrap/sell it and get dual webbers. You'll
> be a lot better off all the way around. Good
> luck anyway and get the vacume gauge and go
> from there. One thing also, if you don't
> like the carb that much check out the JEG'S
> site, they sell some very good carbs and
> some are better for the Z than a average
> store bought Holley.
 

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> My 73 came with the Holley 4Bbl conversion
> by CarTech. Problem is setting idle. Anybody
> have the same.

I do have the same, i tried to e-mail you but it didn't work. E-mail me......I know how to do it on mine, i'll send a few pictures too to point it out. Thanks.
 
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