[Hazieview]

Excellent replies fellas. Y'all definitely go me thinking for sure so Thank y'all! Lol.

I have heard that the smaller 600 cfm Carb might be easier to tune for the reasons suggested by Wilkin250r. I also agree with Desert1957 in the since that I will probably never make the peak HP that my motor is capable of if I choose to use the smaller 600 CFM carb.

So my sb400 isn't anything special. I never intended to push more than 5800 RPM. I know more power can be made but my pockets aren't that deep and the gains would be minimal. For now I'm just plan on having cruising efficiency and maxing out the 600 cfm Carb at the same time. Lol. My motor isn't broke in yet so maybe I will step it up to a 750 cfm Carb after I get it broke in.