Author Topic: Circuits & their impact chart  (Read 1962 times)

Offline Shark Racer

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Circuits & their impact chart
« on: February 14, 2013, 05:33:15 PM »
Has anyone created a chart like this? I think it would be great for helping to understand how a Quadrajet and its various circuits work.

I know that it's not as simple as a Holley or a Keihin, but here's a few examples:





I know that the order of effectiveness is basically the mixture screws, transition slots (determined by tubes and DCR), primary rods (with impact from jet), primary main jets, and then secondaries and their multiple steps of thickness based on AV angle.

What I'm curious about is when the systems cross over, at what point does one system become less effective than another? IE if you're idling at 700rpm, your mixture is determined by the IMS (and the DCR/tube), but does the IMS have any effect at 1000 RPM?

Cruising down the road at 2000 rpm you should be well into the primary jet/rod combo and I would imagine the transition slots have much, if any effect.

I have a pretty good image in my head of how the various circuits work, but I think I would have been jumpstarted in my understanding with a chart like that. Maybe not. :)