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Author Topic:   qjet ??
ryan
Member
posted June 16, 2003 09:58 PM
Under 3000 rpms it sounds like its loading up but it seems o.k. out on the track. Checked the plugs and it they are a light brown color. We have tried to jet down but it didn't seem to make any diffrence. What else do I need to look at? Friend of mine says he was richer than I am and we ran pretty much the same motor.
p.s. it has been modified.


KPLugnut
Member
posted June 17, 2003 09:13 AM
What vacuum reading are you getting at idle, and where/how is the idle circuit set up (mixture screws, transfer slot exposure, etc)?
You mentioned it's "modified", but how much has been done, and where, and why? The Quadrajet is very finicky with the size of its idle feed restiction sizes, power piston spring tension (which affects primary rod actuation) and several other things on the primary side with affect idle quality.

Just some things to consider...

KP


ryan
Member
posted June 17, 2003 05:46 PM
I am not the carb guy in our group so I can't give a lot of detail. I don't much was done to the primary side except holes drilled to make it idle better and I THINK the p.p. spring had a coil cut off of it. There could be more that I don't know about. Never checked the vacumn and right now the intake is off so thats out of the question. I would guess that it doesn't have very much vacumn. Can you give me a checklist of what to peek at. Thanks


KPLugnut
Member
posted June 18, 2003 09:08 AM
Well, firstly, I'd look into what primary jets and metering rods are being used, in comparison to what secondary rods and hanger are in there and we can go from there.
If it's idling ok, after the drilling of bypass holes in the primary butterflies, then the idle circuit probably isn't too far off, but could still be set too rich with the idle mixture screws. How far out are they turned?
You could try closing them each a half turn and see if that leans it out some on the idle side.
Without specifics on what jets and rods are in it, I can't add more suggestions than that, really.

KP

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