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Spark plug reading and Edelbrock RPM manifold

Just for the heck of it I’m going to change my idle air bleeds from a 70 to a 78 and see what effect it has on my idle adjustment I’m only out 1/2 to 3/4 turns out on my idle screws. My secondary throttle blades are closed and my primary blades are just barely exposing t slots. AFR at idle is 14.4 at 800 rpm.
 
Me, I would've used a Holley Street dominator manifold. ( Years ago, we would've used a TM6 )
 
Me, I would've used a Holley Street dominator manifold. ( Years ago, we would've used a TM6 )

IMO...
Perhaps an open plenum manifold, such as an Edelbrock (aka "Eddy") Torker or Torker II, would allow for more even fuel mixture distribution as the manifold runners are somewhat equal length. After the initial pressure drop due to expansion of the air/fuel flow exiting the carb, the mixture will retain its uniformity from plenum to cylinder head port, providing equal mixture continuity. Just my opinion of course...
BOB RENTON
 
You're going in the right direction:thumbsup:
(They do look a little late on timing. I'd add 2-4 degrees before any more carb adjustments to get the marks more in the bend area of the strap, just watch your total).
 
You're going in the right direction:thumbsup:
(They do look a little late on timing. I'd add 2-4 degrees before any more carb adjustments to get the marks more in the bend area of the strap, just watch your total).
My initial timing is at 14 my total is 35, but it’s not all in till 3,000rpm. I’m cruising between 2,500 and 2,800 should I still add 2-4 more initial?
 
My initial timing is at 14 my total is 35, but it’s not all in till 3,000rpm. I’m cruising between 2,500 and 2,800 should I still add 2-4 more initial?
I would, since you're in carb tuning mode anyway.
The plug on the right in your latest picture shows nice clear timing marks in the ground strap. The mark closest to the tip is the initial timing indicator, and the mark nearer the base is total timing. The initial mark should end up middle-ish of the bend, and the second mark will move closer to the base of the strap as well.
Maybe it's kind of nit-picking at this point, if it's running good for you, but with a little more initial you may find your plugs running cleaner and the carb more responsive to tuning changes.
 
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