Try them and let us know I did some air cleaner testing years ago when I lived in Hesperia, we dyno tested in Ontario 1 block north of the 60 Frwy, two stock 6 pak air cleaner elements stacked on top of each other with the lid on was worth 8 HP compare to one single element No air cleaner elements with the stock six pak air cleaner based left on the carbs was worth another 5 hp at 5500 RPM Using the carb. spacer will increase the plenum volume, which should help make more HP and torque, maybe not a bunch, but some gain is better than none