Which air cleaner is legal for D 256 2 Executive Order, for the Rochester QuadraJet? 1980 C30 5.7L engine. (LT1, 4 bolt mains, 350 torque flight, mechanical secondaries, vacuum modulated transmission, vacuum advance that I shall be modifying to 6° locked, base timing 4°, mechanical advance curved to 34° at 4200 RPM. It requires premium fuel, and has no EGR, but does have a smog pump.