New best 60'

The carb has a BLP BX4 main body with a 1.59" venturi and I'm thinking it's to much on the hit.

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I’ve never tried one of the BLP bodies...... that being said, a 1.590” Venturi 4150 carb seems pretty big for a motor that size.

My ported old school annular 850, which has a similarly sized Venturi, requires a certain level of “finesse” on the throttle pedal to get a really clean hit.
If you stomped on it fast, it would act just like yours in that video.