Quadrajet Tuning
Thread Starter
Instructor
Joined: Apr 2006
Posts: 243
Likes: 0
From: Canton MI
Quadrajet Tuning
I am too young to have tuned many carbs before. Can anyone tell me how to properly tune my carb or point me in the right direction on where to look for information?
I have managed to mess with it enough to get it well out of tune. Any help is well appreciated!
I have managed to mess with it enough to get it well out of tune. Any help is well appreciated!
Melting Slicks
Joined: Aug 2003
Posts: 2,135
Likes: 2
From: Dayton Oh
Lars has a great write up and should be a big help to you. The following will get you back on the road until you get a chance to dig into Lars. Of course the following assumes you've not had the carb apart and have only "adjusted" the idle mixture screws. Before I get flamed let me be the first to say that this is almost Bubba and is only intened to get you close.
1) Remove the air cleaner
2) Start the engine and let it come up to normal operating temp and ensure the choke has fully opened
3) Stop the engine and run both idle screws all the way in. Count the number of turns that it takes since this will be your fail safe point in case you have to return to it.
4) Back each idle screw out 1 1/2 turns
5) Restart the engine. If it will not start, then back EACH screw out another 1/2 turn. Keep repeating this until the engine starts.
6) With the engine running, slightly cover the choke area of your carb with the palm of your hand. If the RPM's increase then the carb is lean and will need EACH idle screw backed off another 1/2 turn. Keep repeating this process until the RPM's do not increase.
The idea is to have each idle screw set exactly the same way.
Hope this helps.
1) Remove the air cleaner
2) Start the engine and let it come up to normal operating temp and ensure the choke has fully opened
3) Stop the engine and run both idle screws all the way in. Count the number of turns that it takes since this will be your fail safe point in case you have to return to it.
4) Back each idle screw out 1 1/2 turns
5) Restart the engine. If it will not start, then back EACH screw out another 1/2 turn. Keep repeating this until the engine starts.
6) With the engine running, slightly cover the choke area of your carb with the palm of your hand. If the RPM's increase then the carb is lean and will need EACH idle screw backed off another 1/2 turn. Keep repeating this process until the RPM's do not increase.
The idea is to have each idle screw set exactly the same way.
Hope this helps.
