MGB Exhaust Systems - Sports Stainless Steel with Standard Size Centre Silencer - 4 Cylinder A variation on the three piece systems in stainless steel listed above, including the RP1407SS tubular manifold which replaces the standard manifold and front pipe and couples straight to the centre box.<br />Overall dimensions and performance of the silencers is similar to the specifications of the car’s original mild steel exhaust system, although the note is likely to be sportier and there will be some degree of increase in cabin noise.