Thread: 650 double pumper

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went to check the fuel level on the secondarys ...and no fuel flow..The nut who had this engine before clamed good gas mileage..guess so with a plug in the fuel line between the front and rear bowl. Replaced the line , now heres the question . What is the prossess that you guy's use to set and balance the mixture ( not float level)

IF it's an automatic car would you follow this up with a final idle adjust in gear and maybe recheck the timing? What about the accellerator pumps in the front and rear? Do you set them loose or at a sertain position ( or TAE until it just rev's at the hit of the throttle). if the engine is cammed over 500 /112 over lap do you still use the vacume gauge at idle

If your running a duel plane manifold Denny's procedure will work good for you, but I have found it doesn't work well on an open plenum or single plane manifold. What I have found on a single plane manifold is you can close off completly on one of the circuits and the car will still pretty much idle the same especially on the four corner idle circuits carbs.
For a single plane manifold I start with all of the idle mixture screws at 2 turns open then make equal adjustments towards the closed position on each screw from there a little at a time. Use the vacuum guage method as Denny listed. One thing I have found on a larger cammed motor is I usually have to run the idle mixture a little rich with those double pumper holleys to get good throttle response, might just be me though.
One thing two if you can't get your motor to idle low enough to stay in the idle circuit as Denny mentioned you can drill a 3/32" hole in the primary throttle plates, this will get the plates back into the idle circuit.

it's a single plan air gap EDLE. I am sorry that my question was confussing and unclear. I was just woundering if we all did it kind of the sme or have we found little tricks like the 3/32 hole. I have seen guy's make the slit longer but not drill a hole.