Which do you think is better? Open elements are the least restrictive and take in more air, but the air is much hotter. Cold air induction takes in less air, but the air is colder, and therefore more dense. Of the two, which do you think makes more power? My vote goes to the open element. What do you think?

 

That's an old debate. Personally, I didn't have any problems with an open element at the track because I kept the engine pretty cool while running out there. However, driving around on the street, the open element wasn't so great in stop & go.

Also, during warm-up, the warm air from the exhaust can aid throttle response (eliminate off-idle stumble).

Forced air will make more power at speed than an open element. The question is whether our factory carb system qualifies in that regard.

But, without a doubt, the single snorkel air cleaner looses in the power department.

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This is one of thoses questions that brings up more questions.
An open element is cheap and far superior to the single snorkel. Now if you go to a cold air induction your supposed to get more air than a single snorkel and its supposed to be cooler yet limited at low speeds. Heres where the hampster fall off the wheel in my head
How much air is nessasary and how much is too much? An open element doesent force air down through the carb it takes what it needs. A cold air is bascily a ram air "depending on placement". How much does an engine realy need? If it gets too much air it will run lean and is there really a way to tune for low to high imput? Ive messed with my gokart on this and cant find a good solid seting for a cold/ram air thast make power all around. A car is alot different but they opereate on the same princeples.
Yea you laugh "gokart" but its cheaper to try things out on and results can be felt imediately.
SSC

 

There's no such thing as "Ram Air" on the street (or even the strip for most cars) except in advertising brochures. There's also no such thing as "too much air", it's simply not possible. Too little air, or too hot air (same thing - too few air molecules) very definitely is a possibility however.

CAI is always better, as long as the ducts aren't restrictive. The best all-around system for either a carb or TBI one of these cars is the dual-snorkel CAI system on the L69 Z28s. For TPI it's a little motre specific to the system (MAF or SD) and the body (Camaro or Firebird).

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"So many Mustangs, so little time..."
ICON Motorsports

 

RB83L69, If this is true "no ram air on the street or strip for most cars" than that throughs my whole world into confusion . A cheap definition for ram air is forced induction "not to be confused with super/turbo chargers which also produce forced induction. That means air is pushed into the engine faster= more air, slower= less air. My Pu had a ram air type setup from the factory, snorkel going to the front of the truck to the grill with no restrictor cap on the front. By all means this should be considered ram air right? I do very much agree aboout the CAI being better because it has a unlimited supply of fresh non turbulent air that the engine can sip at on demand, not only that but it looks cool. To much air is just one of my toliet theories on a CC car the computer would conpensate with the proper amount of fuel but on a non CC car it is possible to get more air than than can be properly mixed with fuel "lean".
This is not intended to flame in any way. It was inteded to furter explain my toilet time theories
SSC

 

I believe that if you actually calculate the increased air density produced by "ram air" even at the front of a pickup truck, you'd find the effect negligible (like less than 5%) at speeds less than 100 MPH. If you look at the actual air flow over a hood, you'd see that there is a layer of air that moves with the car, about 1½" thick; so if you were to use a front "scoop" (like what you'd get if you opened up the back of the depressions on a Z28 hood) you'd find even less of an effect than that. The duct you describe for your pickup is a pretty decent system, except that it's a bit small for a deep-breathing engine. 2 such scoops would be great though. The thing that makes them good is the cold air, not the "ram" thing.

But in any case, gasoline is metered by a carb in proportion to air flow. So if more air flows through the carb, then it will produce a higher signal in the venturis, which will produce more fuel delivery. So the mixture will remain correct. The only reason it might deviate is if the carb is jetted lean to make up for thin hot air coming in (same as high-altitude correction), and you hook it up to dense cool air with no jet changes. If the carb is properly calibrated for ambient temp (density) air, then there will be no lean-out problem.

Check out some of the books on such subjects; a couple of good ones are Doug Roe's Quadra-Jet book, and Alex Walordy's Holley book. They both have quite a bit of general carb theory in addition to specifics about the particular design of carbs they talk about.

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"So many Mustangs, so little time..."
ICON Motorsports

 

Check out some of the books on such subjects; a couple of good ones are Doug Roe's Quadra-Jet book, and Alex Walordy's Holley book.
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I'll do that
SSC