The single snorkel air cleaner housing, its design, shape and filter size have everything to do with clean & quiet operation (with minimal maintenance) and nothing to do with "performance" beyond efficent operation. You'll note that in the pre-emissions cars the snorkel is correctly angled forward so as to catch hot radiator air; first, to help the engine warm up (fuel atomisation) and, second, to keep carb icing away. An extra-heavy car with numerically-low rear gears (like an Imperial) just ain't gonna REQUIRE a great deal of air (especially with restrictive exhaust manifolding/tubing; like an Imperial) as the carb can only flow as much fuel as the vacuum signal from the motor will indicate. That is, it accelerates slowly because: 1) mild cam; 2) restrictive intake/exhaust 3) tall tires/high gears 4) smallish carb 5) Real, REAL HEAVY (like an Imperial) Something like this needs: a) large cubic inch displacement b) high compression ratio c) tight [low] stall torque convertor, because, it can now have a carburetor very sensitive to slight throttle changes [driver perceives less effort], quiet intake and exhaust [same; plus car interior quieter], motor operates "inside" of envelope given it: ALL TORQUE. That's all the old luxury cars ever really did was to torque around town. This is why, with the end of high compression they turned into slow, gas-sucking pigs in comparison. Put an open air cleaner housing on board and the noise level goes up, (big deal), but mid-range acceleration/towing ability goes up. Add dual exhaust and you're starting to get up towards the cam/convertor/gear combination potential. Just be aware that with a stock carb fuel mileage can go down w/o re-tuning, and the timing curve should be changed for optimization. (And it'll take longer to warm up. Read about carb icing, too.) Ross