The "Blue Thunder" thread had led to this inquiry;



Disregarding the futility due to back pressure inherent in any street-type exhaust system, aside from "Extrude Hone" type modification (not likely available?) and port/gasket matching, is there any practical way (ceramic internal/external coating perhaps?) to improve the flow of OEM manifolds?

6 VOLTS/POS. GRD. NW INDIANA