best air filter?

[Toronado]

what the best air filter is there a big difference between:

1. open element 14x3
2. single snorkel outlet
3. dual snorkel outlet
4. double stack open element 14x6

supposedly the stock one Im running (single snorkel)
can only flow a max of 550 cfm, with a 750cfm carb
now that doesnt make sense to me, GM must know
why its set up this way. I know about the air temp and density of oxygen,
but the snorkel is only a foot and half long and really does not
get fresh air. I could run ducting to the front bumper for cold intake which I done on other car but the ducting never looks good and is allways in the way-inless its factory cold intake.
Is it really true these OEM snorkels are limited to 550 cfm's?
Im very limited on hood clearance, toronado has a special intake manifold
because of such little room:(, makes me wanna cut a hole in my hood
and mount a cowl:)

[Schurkey]

Open elements (unless specially baffled) will suck heated underhood air; and should be avoided.

One or two snorkels doesn't make any difference IF the snorkel area is big enough.

Given any choice, the snorkel should be ducted to outside (ambient temp) air; and the carb jetted to suit.

My '66 Toro has an OEM air cleaner housing from a newer Toro--a '74-to-'77; or something like that.

Has clearance for an HEI; and is formed to accept a cold-air duct hose.  Had to move the reservoir for the windshield washer, though.