Flooding at Cold Start, Edelbrock 1407 on a 383

[gruveb]

I'm hoping someone can point me in the right direction. Here's the problem and the pertinent background:

383, 10:1 compression, dynoed 420 HP and 450 tq, it's this motor here: new motor.

I have a new Edelbrock 1407 that I put an electric choke kit on.

When it's cold outside and the motor is cold the motor floods badly upon start up. To start, I hit the gas once to engage the choke and then start it. It'll stumble for a few seconds and stall. Crank it again and it stalls again. Suddenly, it's flooded. If i'm lucky enough to get it to run, the choke is functioning properly. The mixture screws are set correctly (when warm) and the timing is 14*.

When I had the smaller 600 carb on, none of this happened.

I've checked the float height, it's fine. I put on a fuel pressure regulator, it's 5.5 psi now.

Any ideas?