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Old 07-08-2011, 11:04 PM
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typical q jet....or?

i have a 72 satellite 318 with a 270 cam, edelbrock intake and a qjet. the q jet has the typical when i stomp on it it completely dies for a few seconds then takes off. pretty typical from what i have read. the problem is this carb came off a chevy truck and was put directly on to my car and the carb did not have this issue prior to being on my car. aside from rebuilding and rejetting is there any other possibilities that could be related to having this carb on my mopar?
also when i stomp on it i notice it takes about 2-3 seconds for the secondaries to open up, again im unsure if this is typical.

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Old 07-08-2011, 11:10 PM
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It needs to be tunes for your engine. Simple as that. Q jets are good carbs but have to be tuned near perfectly to perform like u want it to.
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Old 07-08-2011, 11:11 PM
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i do get that, my question is what would make the secondaries act up on one motor but not the next?
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Old 07-08-2011, 11:17 PM
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Hopefully the forum members will chime in with the exact information you are looking for. However, in the mean time, if you don't mind doing some reading, this article on troubleshooting and tuning Quadrajets may be of help: "Quadrajet Info by Lars ".
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Old 07-09-2011, 12:01 AM
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Looking at the passanger side of the carb in direct line of the secondary butterfly rod you will notice the area is rectangular shaped, beind this casting is a spring. If you look close you will see a standard screw (straight) slot on the underside of (the top cover) that little rectangle is an allan head screw that is the "locking" screw for that rod and spring. If you carefully loosen that allen head screw and with a screwdriver in the slotted screw. (This is important becasue if you lossen that locking screw too much that adjusting screw can and most often does take flight.) That secondary spring can be adjusted. Clockwise to tighten the spring and counter to loosen.

I set mine to a "baseline" when I have the carb off. I loossen the locking screw and adjust the spring until it just touches the pin that sticks out of the rod behind thta little rectangle area. Once it touches I tighten the ad=justing screw 1/4 to 1/2 turn and lock it down. If I recall correctly the rebuild sheet in a Quadra-Jet rebuild kit calls for 3/4-7/8 once the spring touches that pin.

This will allow the secondaries to open easier=sooner.

If the carb has a rear pull-off canister it may be in the way to adjust the spring. Here are a few pic's....it is to the top and left in the first pic, it can be done with the carb on but it is much easier when it is off the manifold.



Hope this helps.
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Old 07-09-2011, 12:02 AM
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Quote:
Originally Posted by badknuckles
i do get that, my question is what would make the secondaries act up on one motor but not the next?
Its because of the way they are set up. They open when the engine needs them. But since it is tuned for a different engine, it may take longer for your engine to generate the vaccum needed to open them. Or it may just be that the primaries are sufficiant enough for your engine. Cant know exactly until you tune it.
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Old 07-09-2011, 02:46 AM
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Thank you guys for the great info,i appreciate it
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Old 07-09-2011, 12:35 PM
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Different gear ratios,weight,and transmission among other things effect carbs.
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Old 07-09-2011, 03:57 PM
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definitely not normal,
secondary air valves need adjusted

and a couple other things yep
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Old 07-10-2011, 12:24 PM
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Quote:
Originally Posted by muddi1
Looking at the passanger side of the carb in direct line of the secondary butterfly rod you will notice the area is rectangular shaped, beind this casting is a spring. If you look close you will see a standard screw (straight) slot on the underside of (the top cover) that little rectangle is an allan head screw that is the "locking" screw for that rod and spring. If you carefully loosen that allen head screw and with a screwdriver in the slotted screw. (This is important becasue if you lossen that locking screw too much that adjusting screw can and most often does take flight.) That secondary spring can be adjusted. Clockwise to tighten the spring and counter to loosen.

I set mine to a "baseline" when I have the carb off. I loossen the locking screw and adjust the spring until it just touches the pin that sticks out of the rod behind thta little rectangle area. Once it touches I tighten the ad=justing screw 1/4 to 1/2 turn and lock it down. If I recall correctly the rebuild sheet in a Quadra-Jet rebuild kit calls for 3/4-7/8 once the spring touches that pin.

This will allow the secondaries to open easier=sooner.

If the carb has a rear pull-off canister it may be in the way to adjust the spring. Here are a few pic's....it is to the top and left in the first pic, it can be done with the carb on but it is much easier when it is off the manifold.



Hope this helps.
Best reply right here, was going to say the same thing. I like to tighten them quite a bit, then gradually loosen the spring tension to where they just bog. Turning the screw in 5 minute intervals as if you were looking at a clock helps to know where you are.

As long as it is running fine except for the bog, this is all you will have to do.
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Old 07-10-2011, 03:52 PM
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I adjusted them and now it still bogs but also seems like its loading up.time for a rebuild.
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