adjusting q jet primaries
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Re: adjusting q jet primaries
If this is a computer-controlled one, don't bother. They have virtually no "authority". I'm not sure why they're even there. I just set them to 7 turns out (they're an EXTREMELY fine thread) and leave them there, on every one of those I ever build; then tune the idle with the IAB valve, which has MANY times the amount of effect that the screws do.
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Re: adjusting q jet primaries
I think it's more like 3-4 from seated. You only need to move them if you run out of adjustment room on the iac.
And they're not hex. I dont remember what it's called, it's more like a rectangle. You get the bit when you buy one of those flexible-shaft carb adjustment screwdrivers. Or if you take the carb off you can use pliers to remove them then saw a notch in it to use a flat head screwdriver.
And they're not hex. I dont remember what it's called, it's more like a rectangle. You get the bit when you buy one of those flexible-shaft carb adjustment screwdrivers. Or if you take the carb off you can use pliers to remove them then saw a notch in it to use a flat head screwdriver.
#6
Re: adjusting q jet primaries
Alright Sparky, I just wanna know what the **** I'm doing. The guy who rebuilt my Q jet, told me he put smaller jets in it for better primary performance. He would adjust it if I got frustrated, but I would like to do it myself. It does have good throttle response. Better than before.
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Re: adjusting q jet primaries
I think it's more like 3-4 from seated. You only need to move them if you run out of adjustment room on the iac.
And they're not hex. I dont remember what it's called, it's more like a rectangle. You get the bit when you buy one of those flexible-shaft carb adjustment screwdrivers. Or if you take the carb off you can use pliers to remove them then saw a notch in it to use a flat head screwdriver.
And they're not hex. I dont remember what it's called, it's more like a rectangle. You get the bit when you buy one of those flexible-shaft carb adjustment screwdrivers. Or if you take the carb off you can use pliers to remove them then saw a notch in it to use a flat head screwdriver.
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#8
Re: adjusting q jet primaries
OK, the double D. The bits are not marked, but I noticed four of them are called hexes, and one double D Two are male hex bits, and to female bits which are hex design of different sizes. The other must be the double D. Why do you recommend turning them in first and then backing them out?
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Re: adjusting q jet primaries
You turn them all the way in so you know your starting point. 3 3/8 yes that was the official number for my 85. I'd usually put them at 4 or 4.5 because the iac would be a little too far in on mine if it was at 3 3/8, but my shortblock had been replaced so maybe it had a hungrier cam.
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Re: adjusting q jet primaries
No, it's just that when you have your dwell meter hooked up, adjusting your IAC to get your dwell cycle where it should be, if your IAC is turned in as far as it can go and your dwell still isnt right (I dont remember anymore whether you turn it in to increase or to decrease dwell), thats when you back the front screws out then readjust the iac. I think the manual says try about 1 additional turn at a time.
Theres something else that people do to increase fuel flow on the primaries, they adjust the lean stop screw or give the needles more than 1/8 travel or something. I neverm essed with that because my car didnt have any part throttle flat spots.
Theres something else that people do to increase fuel flow on the primaries, they adjust the lean stop screw or give the needles more than 1/8 travel or something. I neverm essed with that because my car didnt have any part throttle flat spots.
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