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Wed Sep 17, 2008 6:45 pm

Have new dual kadrons on my 73. Attempted to set the mixture according to lowbugget. When I turn the mixture screw all the way in, the RPM's go up. When I turn it out, it stumbles and tries to die on me. This is opposite what lowbugget says should happen and everything I've known. Any ideas out there? 009 distrubutor carbs not set up for vacuum advance

Wed Sep 17, 2008 7:22 pm

If it is running way to rich, i.e. gas poring out of somewhere in carb, idle jets way to big… reducing extra fuel will make it run better, you do not say weather the carbs are new/ new to you /used rebuilt…

It runs better when you turn the screws in because your mixture is way off. To tune a duel carb setup you need to have a good air flow meter and be in the ball park as to the jetting, & have carbs in good order; if you provide more information as to your setup maybe someone with the same carbs can give you an idea about where to start with the jetting…

Wed Sep 17, 2008 7:22 pm

Cheycowboy wrote: Have new dual kadrons on my 73. Attempted to set the mixture according to lowbugget. When I turn the mixture screw all the way in, the RPM's go up. When I turn it out, it stumbles and tries to die on me. This is opposite what lowbugget says should happen and everything I've known. Any ideas out there? 009 distrubutor carbs not set up for vacuum advance

If you screw them all the way in what happens does it shut off.... Do you have any vacuume leaks? Theres a poss. that the screws are way to far out to start causing it to be rich making the engine flood out.. If you screw them in it leans out the mixture so it could be closer to where you need to be.

Thu Sep 18, 2008 8:26 am

As far as I can tell, there are no vacuum leaks. It runs at its best if the mixture adjustment screws are screwed all the way in. It doesn't try to die until I try to back them out. The setup is only 2 years old. I had the shop put them in and it really hasn't run right since they put them in. All the timing/idle/mixture adjustments seem impossible to do. Even the idle is set as far as they will go.

Thu Sep 18, 2008 9:27 am

What's your fuel pressure? Have you installed the Holley fuel pressure regulator? Tuning Kadrons starts with those things.

Fuel pressure should be 1.5 psi or a bit less. Even the stock mechanical pump puts out more than that.

The 'dial' style regulator will only starve your motor when you get to 4th gear if it's set to 1.5 psi, as it won't flow enough at 1.5 psi to feed a Bus.

I have a set of AJ's Kadrons as well (vacuum mod and T4 SVDA). They came jetted a bit fat for my combo, but I was asking them to make a big guess about my 2.0 and an unfamiliar to them cam.

Thu Sep 18, 2008 9:36 am

I haven't checked the fuel pressure or air flow, guess I need to do that today. Will get back to ya after that's done.