Ram air busted: because it does not exist, for the following reasons:
- Air is incompressible at any automobile speed (I.e. speeds less than Mach 0.3).
meaning that the kinetic energy of the air cannot be used to compress the air and
raise the static pressure.
- The “ram air” nozzles commonly employed on automobiles tend to be the wrong
shape. A divergent nozzle is required for ram air. Straight-profile scoops cannot
provide a ram air effect.
Select one of the two types of intakes, warm air, or cold air. Beyond that its just about
looks."
Reference https://www.physicsforums.com

Intake air temps: The rule of thumb with the average V-8 is 1 hp for every 10 degree (F)
drop in intake air temp. That works out to about 1% for 30 degrees.

Cold air kits: Busted (sorta)
https://youtu.be/gCi2yo4UqPI

Most interesting was no air filter made no power gain vs using an standard factory air filter.
Makes you think twice about those K&N claims we all seen. Fascinating stuff.

Yet these guys dyno tested a ~400hp mopar big block and found a 14hp difference between a generic 3" paper air filter in an open element air cleaner versus open carb. Clearly these results would vary with engine air intake demands as well as the efficiency of your existing air cleaner, but the filter they used for their dyno testing was pretty standard in the hot rod community.

http://www.hotrod.com/how-to/engine/1307-mopar-engines-power-vs-luxury/

My 95 5.2 magnum in a jeep grand cherokee just had a generic factory cold air intake just like you would see on any other modern vehicle. IIRC air was drawn in from the headlight bucket area.

My memory is a bit fuzzy,
but on the Spitfire airplanes "reverse ram air" was applied to the engine exhaust manifolds and a worthwhile gain in airspeed resulted.

It should be remembered that if two otherwise identical cars
capable of 100+ mph terminal speeds in the quarter
drag race repeatedly,
with the two drivers swapping vehicles after each race,
if one car gets fitted with an air intake that gets 2% gain from cooler air and 2% gain from ram air,
you would expect that car to win more than 50% of ten or more races.

There's something else at foot there. We did that at the track too. Difference in ET was statistically insignificant with a 400 big block in a 74 Satellite Sebring Plus. I believe the ET's were a consistent 14.2 give or take a hundreth.

Meredith effect

Air cleaner tests are no good with out carb mixture changes too. This rings true with any induction side testing you do.

We must have a failure to communicate here. I wonder if those egg heads are getting hung up on the street meaning of "ram", to me in our application, it only means raising the general air pressure in the vicinity that feeds the carb or whatever, anything that does that in our hobby qualifies to me as "ram", if we aren't splitting hairs. We raise the inlet pressure all the time, sometimes lower it un-intentionally, hence all the comments as to the carb needs tuning for fair comparisons. I pretty much lost interest at the "Incompressibility" at less then mach 3 comment.

You get cold air in either case - scoop sealed to the base plate/carb or not - but you pick up power by having a PROPERLY designed scoop sealed to the carb. A poor design can actually SUCK air OUT of the scoop.

On my car in C/SA back in the 70's going 115 or in SS/GA going 125 - hooking up the scoop to the air cleaner baseplate has always produced more power - shown in lower ET and higher MPH.

In fact John Baumman (Chrysler carb expert) jumped in my case when I ran slower at a Milan Test Day after a change in manifolds from the old factory six pack to the STR. When I took the hood off the car and he saw no baseplate he said "there is your problem". I had to "modify" that OE 69-1/2 baseplate with a hacksaw - added some sponge to the outer portion to seal it to the hood - and picked up a solid tenth and 1-1/2 mph. But don't believe any one person - do a base line test - if you have a scoop - attach a sealed base plate to the scoop and make a couple passes then take it off. See what happens. Don't give up because some people offer up invalid assumptions and opinions - TRY IT FOR YOURSELF.

.(point)3 mach. Around 230mph.

This is true of people. However the science of fluid dynamics doesn't lie. Great conversation though, interesting opinions

They may not lie - but they are subject to interpretation. If all else fails - use scientific instruments. Hook up a manometer to the scoop - like Chrysler did back in the day. Yes - the primary purpose of the street scoops were for fresh (colder) air - the race packages were tested and proven to provide "ram air".

(Don't waste yer time...


He's already made-up his mind...)


'Ram Air' is a myth...

FD trumps all...

I think it stands to reason that without a carb to hood seal, between the speed you put on and the fan turning 5000rpm, the engine bay is enough of a high pressure zone to overpower your tiny scoop.

Lets not forget that cars fun faster at lower elevations, proving that the slight difference in air density does make a difference.

I wonder why the old pro stock cars had that giant air scoop on their cars,not real aero are they?

There is a lot in the design ov the air cleaner itself. The difference between running a stub stack atop the carb without anything else and running various air cleaners, from stock design to cheap aftermarket design, from 3x10" to 2x14" to 5x14", from paper to K&N were notable enough for me to ditch the thing altogether and risk sucking whoknowswhat down an open stub stack. One ov the many 'tricks' on that car... though you'd probably be mad to daily drive a car with essentially an open carb on any engine you had real money into. Had i been really gambling, i'd have found a way to 'flow' the hole in the hood into the stub stack and then be only sucking in cold air on top ov all else... but that would be literally asking for trouble with an open carb. Maybe for track only...

Now a days the manometer has been changed out for a map sensor mounted in the scoop/carb plate area. Makes it very easy to see if the pressure is above or below atmospheric. If you haven't done this you're just not as dedicated as some other racers. It's always easy to talk theory, results speak for themselves.
Doug

A map sensor doesn't show flow turbulence though. turbulent air thru the carb is not optimal. I might need to make one.

Chrysler seems to have dedicated more money to designing and building long runner intake manifolds, than on ram air/cold air inlets ahead of the throttle blades.

In the end everyone's budget and time is limited.

Getting a high flow rate 25 to 28 inch long runner intake manifold that also feeds all eight cylinders equally appears to provide more bang for the buck for street driving.