Thanks for this, I am just about to install a dual quad, 1:1 setup on my 408, and did exactly that. I jetted carbs down thinking there would be more fuel. I will set them back to standard setting for initial trial. View attachment 1716082221
Jetting (and all fuel/timing adjustments for that matter) should always be made because you observed something. Find a problem, Make a change, observe the result, repeat. You dont ever want to guess or assume.