I had the stock 2x4 with 2-650 eddys and it was rich all the way around.... so I know 2-600's would feed it. And I agree jetting is a work of art and I tinkered a lot with my old setup. I have lots of metering rods, jets, and springs. Also the single plane does have a passage and that's nonsense you'll burn the front half up. You're getting idle circuit fuel which isn't much but it adds fuel.... I agree there will be distribution issues but hell the factory was so crappy the had to stagger jetting to help. I'm gonna run progressive and read the plugs.... thanks guys!