Hi All
Does anyone here port match the intake to the engines on 12a's , let me know your thoughts and if you have done this what the "butt dyno" thought of the porting.
Don

 

The ports ,manifold to engine are not matched so the effects of reversion are lessened . The sound wave pushing gas and air back through the ports when the rotor closes the port . A one inch thick spacer under the carburetor will help .

 

take your inlet off and look how dirty the secondaries are to what he means. They're covered in cack. The primaries dont because of the "step"

it helps efficiency at low (read: streetable) rpms