Originally posted by JonsZX2SR:
The surface was polished and chemically anodized using a method used to promote air flow in jet engine passageways. (I work as a materials/manufacturing engineer in the aerospace & transportation field.) On a flow bench the TB flows +18-20% better than stock over pressure drops ranging from 3-10 in-Hg.
The throttle plate was not given a knife edge finish for two reasons: 1/ I wanted the best transition during tip in and elected to keep the beveled edge with very small radii at the corners, and 2/ the best leading edge isn't a knife edge anyway. the best leading edge actually has a curved surface with compund radii.
Air in a TB works more like air over the surface of a golf ball than air/fuel through a jet engine. Totally smooth is not the way you want to go.
The beveled edge on the throttle plate I can agree with for the leading edge, but the leading edge of the TB housing I can not. Since the transition is not drawing from open air surrounding the edge, the best leading edge will result from the least amount of turbulence. A knife-edge there will create the wanted venturi effect against the silicone or rubber hose adapter going to the CAI/MAF/etc with the least amount of turbulent air. The only other way would be to eliminate this joint all together with a one-piece intake tube/TB/etc.
Still, very nice work.
