I have searched and searched, but I can no longer find the site from back in the old days when this place was just a DORJE Listproc mailing, that detailed a buildup of a CB750A dragbike. Standard drag kit, except for the Rochester Quadra-jet carb on a hand-fabbed four runner intake manifold! Being a drag bike, the frame was modded including cutting the top tubes at the seat and welding new ones on with a hump in them to clear the air-cleaner and carb.
A log manifold just won't give you good performance on a carb bike. Too much opportunity for the fuel to fall out of suspension and puddle on the floor of the manifold. You want to keep the fuel air mixture moving fast and smooth so the fuel stays atomized. Look up extrude honing sometime. It is a process where an abrasive putty is pumped through the manifold. This enlarges the runners for more breathing, but also, as the name suggests, hones out the rough interior of the cast manifold so fuel stays in suspension.
Now, all this being said...try whatever you want to try! I love the "What if I did this to it?" aspect. I like trying new things and learning by trial and error, or success.
