ATM/Holley verses Carter 625 AFB

Mattax said
You dyno guys can explain to me if I'm looking at an AFR calculated off the fuel consumption and a measured or assumed airflow, or from an WBO2.

I ask because these my takeaway from the graphs:
1. This engine will keep increasing power until at least 5100 rpm
2. The Carter didn't loose or gain anything. The engine was given a different air fuel ratio and responded accordingly.
There may be more potential in on the higher flowing carb, but we compare the higher flows with the same AFR.

The other thing that may be a little different is the depression. And this engine might like more manifold vacuum or a little less depending on things like the distribution. The engine with a TR vs. a dual plane on it should (in theory) have pretty good distribution and so be fine with less vacuum which is a potential advantage of a 'higher flowing' carb.
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Those AFR’s are from my O2 sensors. I’ll put the air hat on it next time and get more numbers, but it won’t be on the same intake manifold. It will be a Holley Street Dominator and then a Strip Dominator.

If I’m following what you are asking, then yes the AFR should be the same between any carbs being tested. My carb is pretty fat down low, so I’m sure that hurt torque below peak. And, it may be a skosh lean at the top but for some reason with these O2 sensors it may like 13:1 or a bit more.

Even if I lean the Carter out to get it to 13:1 it won’t make 37 horsepower more.

Edit: the intake is a performer RPM. Distribution is GARBAGE like it always is with a dual plane intake.