[aumoore]

I have a 600 Vac secondary Holley on my 302 and am running a 9" Ford Motorsport round open element air cleaner. I started with the stock paper element that came with the air cleaner. Car ran great but I decided to use a K&N filter. The paper element was about 1.5" tall and I calculated that a 2-1/2" tall element would work. K&N had a 2-3/8 element that worked perfectly.

Did the K&N work? I say it probably added maybe 5-6HP which is barely enough to make any differance.

I did add a turkey pan later and it had more effect than the K&N.I would guess at least 10HP due to a cooler running carburator which heats the fuel less and gives denser fuel. Hence more HP. I think the pan helps direct the cooler air from the scoop directly to the carb and keeps some of the hot engine compartment air away from the intake of the carb.

It is a good idea to put a heat shield below the carb to protect it from the engine heat.