Stock Q-Jet to straight 4bbl swap
03-02-2005, 04:27 PM
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Car: 1984 T/A
Engine: L69
Transmission: 700R4
Stock Q-Jet to straight 4bbl swap
This is just a dizzy question. I guess since the intake manifold I want for my 305 doesnt have an EGR version and I need a new carb anyway I guess I'll just swap to a non computer controled 4bbl. My main question is will the stock HEI work with little mod or do I have to get a vacumme advaced dizzy or does the HEI control the ignition advance? If not, I guess I can just suffer with getting a different intake manifold because I realy wanted to keep the Q-jet.
03-02-2005, 04:45 PM
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Car: 1987 SC/1985 TA
Engine: 350/vortec/fitech
Transmission: T56
Axle/Gears: 3.27 9-bolt
If you swap out the ccc-qjet you'll have to replace the distributor. The timing is controlled by the ecm. Why can't you use the q-jet? What manifold are you using?
The lack of egr shouldn't affect it. I don't have egr plumbed into mine and no worries. I'm pretty sure the ecm's soo was too basic to advance the timing to take advantage of egr under light loads, but I could be wrong. If someone has a better understanding of the sequence of operation, chime in.
The lack of egr shouldn't affect it. I don't have egr plumbed into mine and no worries. I'm pretty sure the ecm's soo was too basic to advance the timing to take advantage of egr under light loads, but I could be wrong. If someone has a better understanding of the sequence of operation, chime in.
03-02-2005, 07:52 PM
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Car: 1984 T/A
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Transmission: 700R4
Originally posted by naf
If you swap out the ccc-qjet you'll have to replace the distributor. The timing is controlled by the ecm. Why can't you use the q-jet? What manifold are you using?
The lack of egr shouldn't affect it. I don't have egr plumbed into mine and no worries. I'm pretty sure the ecm's soo was too basic to advance the timing to take advantage of egr under light loads, but I could be wrong. If someone has a better understanding of the sequence of operation, chime in.
If you swap out the ccc-qjet you'll have to replace the distributor. The timing is controlled by the ecm. Why can't you use the q-jet? What manifold are you using?
The lack of egr shouldn't affect it. I don't have egr plumbed into mine and no worries. I'm pretty sure the ecm's soo was too basic to advance the timing to take advantage of egr under light loads, but I could be wrong. If someone has a better understanding of the sequence of operation, chime in.
03-02-2005, 08:03 PM
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Car: 1985 Iroc-z Camaro
Engine: L69 5.0 HO
Transmission: 5 Speed
Qjet is spreadbore. Holley, Demon, Edelbrocks are squarebore. If you can get your qjet rebuilt and running right, its hard to beat in my opinion. I have my egr disconnected too, but I think it has more effect on denotation and timing than on your carburation.
03-03-2005, 06:25 AM
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You can get an adapter to run spreadbore on a squarebore manifold. It will add some height so make sure you've got the clearance. Still a better option than replacing carb and distributor.
Then you'll also have to get a kit to operate the converter clutch on your auto trans, as the ecm controls this too.
Then you'll also have to get a kit to operate the converter clutch on your auto trans, as the ecm controls this too.
03-03-2005, 05:41 PM
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Car: 1984 T/A
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Originally posted by naf
You can get an adapter to run spreadbore on a squarebore manifold. It will add some height so make sure you've got the clearance. Still a better option than replacing carb and distributor.
Then you'll also have to get a kit to operate the converter clutch on your auto trans, as the ecm controls this too.
You can get an adapter to run spreadbore on a squarebore manifold. It will add some height so make sure you've got the clearance. Still a better option than replacing carb and distributor.
Then you'll also have to get a kit to operate the converter clutch on your auto trans, as the ecm controls this too.
I will just stick with the q-jet and find a spreadbore manifold. I'm just gonna buy a new q-jet instead of rebuilding the old one. Thanks for all your help! : )
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