Need tuning help on 340

It's at 15* initial and likes 20+ initial, of course it's going to be fat at idle.

Give it the initial timing it wants, set the idle mixture screws and move up the food chain from there.

You will get stacking issues when the idle is off. It's fat, so the accelerator pump doesn't need to be where it should be. AP can be lean so you don't have an off idle rich stumble (fat idle covers this) and on up the circuits.

Get the base circuit correct, so that the additional circuits work, providing the required fuel that they are supposed to give it.