Hesitation on PWR

Hi guys and gals.

Its a 2EL automatic on Corolla 1986

Aisan VV carburetor with variable vanturi(needle)

When cold its running fine with almost none hesitation on PWR.
When driving some it begins to hesistate, and i can hear exhaust fire(its often one fire) the car "jumps" a little, it then gets up in revolutions.
It happen each time it goes from green to red(PWR).
When through the hesitation point it works fine on PWR.

It feels like thst something does not open fully thus making car to hesitate but when applying a little more acceleration it goes through that point and works ok.

I must add that I could have had a little to much oil in it the other day, fully synth 3w30.
And I also had oilleakstop added to the engine as I had seen oil dissappear.

Any ideas?