Hi everyone. Just a quick question. I have an Edelbrock X1 cross ram running 6 x 97s. Just starting to dial in the tune. Am I correct in say that the left bank of carbs feed the right side of the engine and vice viser.... I have one nice lean side and one real rich side at present. Cheers Themoonman Sent from my SM-J530Y using The H.A.M.B. mobile app
You answered your own question..! "Cross-ram". Yes, left side to right, right to left. As noted, go out and buy a Uni-Syn tool (a couple different ones available). Complete the following carefully - Read and reread this before starting the task. 1. Remove the carburetors. Yes, remove them... 2. Set all of the idle speed screws the same turns out. I'd start at maybe 1/2 to 3/4 turn out. 3. Using a "small" drill bit (or a narrow 1/4 wide, feeler gauge), adjust each carburetor throttle plates butterflys so they are the "same" amount open. All six have to be the exact same amount open to start this whole adjustment task. Measure what you have now, average it and use that amount to start with. Use care in this step. 4. Reinstall the carburetors, DO NOT install linkage at this time. Verify that they are not at any angle, all are parallel to each other. Measure the throttle shaft centers to verify parallel. Verify that they are tight. 5. Start and warm the engine to full operating temperature, verify the idlespeed is good/normal. Readjust the idle "speed" as required. Adjust EACH carburetor the same amount when completing this task. Use GREAT care in this step. 6. You may need to alter the idle "mixture" adjusting screws. DO EACH carburetor the same amount, in or out, as required. Use care in this step. NOTE: This step WILL alter the overall amount of fuel going into the engine, JUST like the jets do, use care, verify that each has the SAME amount of adjustment, in or out. 7. Now...get out your new Uni-Syn (synchronizer tool). 8. Open the adjustment on the synchronizer tool to about 90% open, (if it has one, some don't). 9. Put the tool on the top of a carburetor (any). Adjust the tool so that the tool does NOT restrict the airflow, but the needle/float move to about the middle of the sight level/scale. 10. Now you can start adjusting ! Check all six carburetors, check all six carburetors...and maybe one more time..! Write down where each carburetor is per the tool. Use care in this step. 11. CAREFULLY, start adjusting the carburetors speed adjusting screws, so that they all read the same amount of airflow per the tool. Watch your idle speed, adjust as required..."ALL six carburetors" need to be adjusted to reset the idle speed. Use care in this step. 12. Recheck all six carburetors, readjust as required until all six are flowing the SAME amount of air. Recheck all six carburetors again. ***ONLY move on if the engine is running smooth, the idle speed is where you want it. 13. Assemble and adjust the linkage. Verify that NO carburetor throttle shaft is pulled open OR forced closed while attaching the fasteners. Use GREAT care in this step. 14. Verify step 13 is completed (and tight) the best that you can do. Take your time on them, readjust the linkage as required to verify that NO shaft is moved during the attachment of the linkage. 15. Get the Uni-Syn/syncronizer tool, and check to make sure you did not change anything during the attachment of the linkage in step 14. Use care in this step. NOTE that even loosening and moving a carburetor on the manifold will screw up the whole system. Misadjusting/readjusting one (1) carburetor will screw up the whole system. You need to start adjusting again. Have fun... Mike P.s. - While completing the "adjusting" task, give the carburetor being adjusted, a small open wack and recheck the airflow. This is to verify that the butterflys are seated as well as can be. If you have loose butterfly shafts...well..!?
Hey Mike. I spent nearly all day following your steps! Awesome Just one other question. I have adjustable jets in all 6 carbs. I have the car idling and starting real nice... it's currently running on the centre 2 carbs and the outer 4 come in at about 2800rpm. I did some tuning with my gas analyzer today to try and get it a bit more on the leaner side. The right hand spark plugs are cleaning up nice and white and the analyzer show a good tune. The left hand side plugs still looking real rich and gas analyzer shows rich to... can I just keep slowly winding in the jets on the right hand centre carb to lean it up...... Cheers BRUCE Sent from my SM-J530Y using The H.A.M.B. mobile app
"I have adjustable jets in all 6 carbs." Do you mean adjustable idle mixture screws, or adjustable main jets? If adjustable jets, you are going to need a method of checking each exhaust port. Either a bung for a lead to the gas analyzer to check mixture or a hand-held pyrometer to check and compare temperature. (Opinion) adjustable main jets are wonderful on a single carb application, but add several degrees of difficulty in a multiple carb environment. Jon.
Hi Jon I have been adjusting the main jets. I have been checking exhaust temp regularly. They are all pretty even now.... the richer exhaust bank was a lot colder but I just leaned it out another 1/8 turn and it bought the exhaust temp up.... Hoping to take it for a drive tomorrow to see what it does... Sent from my SM-J530Y using The H.A.M.B. mobile app
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