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What is the Difference between Ram Air, CAI and WAI?i need somthing to help my little E16I! LoL
 

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bitter old man
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Ram Air uses the inertia of moving airstream to cram extra air into the intake system, usually with an external scoop directing air from outside the vehicle into the intake tract.

WAI, or warm air intake, is a cone filter and bellmouth adapter to suck in lots of hot engine-compartment air.

CAI, or cold air intake, is a cone filter isolated from the hot engine compartment.

Ram air, as a concept, is proven. Ram air, in application, takes testing for each vehicle type. Ram air, even if done wrong, provides the benefit of a CAI, i.e. extra power.
 

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ex-Super *********
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Generally speaking of course:
Ram air: a closed system in which forward movement of the car rams air into the intake tract.

CAI: Cold Air Intake, A system which puts the filter in such a location that it draws cold air into the intake from outside of the engine bay. Hot Shot, AEM, Place Racing.

WAI: Warm Air Intake, a sytstem that draws air from inside the engine bay. Term is mostly used to describe a cone/open filter in place of the normal air box. If you want to get picky the most stock intake sytems are WAI's. We(tuners) use the term to describe the open element set-up. JWT and Stillen POP chargers.

In terms of hp gain, ram air has the most potential for hp gain, but is hard to design and tune. CAI is nest in line for hp, its the easest to obtain since you can find them on the market. WAI comes in last. It is better then a stock set-up due to the fact that it flows better, but it lacks the cold air and tuned leangth benifits of the CAI
 

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99 Problems...
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PatScottAKA99XE said:
WAI comes in last. It is better then a stock set-up due to the fact that it flows better, but it lacks the cold air and tuned leangth benifits of the CAI
I thought the same about WAI but take a look over in the general forum of www.sr20deforum.com see the multi page discussion about how WAI could be better than a CAI

O
 

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bitter old man
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That thread is crap since there has been no documented evidence that a WAI could be better than a CAI. Butt dynos do NOT count as they are notoriously poorly calibrated. What IS documented is that as intake temperature drops, power goes up; it's a law of physics. That right there is enough to shoot down the WAI vs CAI debate.
 

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What IS debatable is the performance gains of the CAI over the WAI. I assume that you read the article and i also assume that you saw that there are people that agreed with your position. So i will further assume that you read the part about those trapping higher and running lower times at the track with a WAI.

So now I will therefore conclude that either you didn't fully read the statements made (i.e. that 1/4 mile times DO NOT equal butt dynos) or you are denying the facts that were presented.

I have a CAI
A WAI is only such when the car is stationary (i.e. on rollers via dyno) at speed it has been proven that because of the airflow through the engine and some custom housings a WAI will remain cool. Also because of the shorter piping vs a CAI response is better.

But since you read the arguments i guess you knew all that and took that into consideration before posting

O
 

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Ok,

I read that whole thread and I guess there figures were off of 90 degrees + weather....Maybe that had something to do with the lack in preformance from the cai....and like you said the wai has better respone because of the less air travel...
 

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this "better" responce you talk about, the physics would say it would be true but IMO you would have to have one hell of a "butt dyno" to tell the difference in an additional 2' of piping. im not debating though that cool air is more dense thus more oxygen thus more power, it just is. once winter is over i will try to make my own CAI like if seen pics of in this forum.
 

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to me, saying that youv'e got 3 to 4 tenth at the track using a WAI is absurd. IMO there are TOO many variables at the track, hell you can lose a tenth just shifting at a different RPM. the only way is to dyno.

before everyone jumps my shit about calabration(sp?) all else being equal it doesn't matter if it is off 20hp as long as you use the same dyno and make runs as close as possible the gains/losses will be relitive.

tonight i going to try experiment. i have an indoor/outdoor thermometer with a lead to take out side. i will put one end at my WAI and the other at the place ment of anyones choice. i will record the difference.
 

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Show me the dyno slips.

Quarter mile times have too many variables. I'm not saying it's not true, but I highly doubt it.
 

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Geo said:
Show me the dyno slips.

Quarter mile times have too many variables. I'm not saying it's not true, but I highly doubt it.
Back to back dynos please
 

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It would seem that I have not made my point clear so i will try to do so now.

No one (me) is disputing that a WAI will make LESS hp than a CAI on the dyno.

What some are saying is that in real world driving and 1/4 mile the effects of a CAI could be lessened to the point where a WAI becomes essentially a short ram CAI (because @ 40mph air is entering the engine bay)

So if this is further not clear pm me and tell me what I am not expressing.

But if this is clear then you will understand when i say a dyno will not prove what people are saying about a WAI.

O
 

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onyxeros said:

What some are saying is that in real world driving and 1/4 mile the effects of a CAI could be lessened to the point where a WAI becomes essentially a short ram CAI (because @ 40mph air is entering the engine bay)
I agree with your statement to an extent. You have to remember that its all relative....its true that while driving there is cooler air entering the WAI, but there is also cooler air entering the CAI. I say relativity because depending on outside temperature, and the temperature/density at which the engine utilizes cold air, a CAI may or may not increase the gains by the same amount as the WAI would. So a 10* decrease in both intake temperatures might cause a 10% difference in power for both on one day....but a 10* decrease may yield a 10% increase for a WAI, but only a 5% increase for a CAI on a colder day....based on how the engine utilizes the cold air.

Also, a car with a header will have better gains from a CAI than the same car with a WAI in terms of the % increase in power...because the heat from the header will cause an increase in engine bay temperature. Its all relative.
 

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bitter old man
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What the hell is a "short ram" intake? There is no aspect of our underhood intakes that could be considered a ram system.

For those in the WAI camp, remember that the vast majority of air molecules under your hood has passed through the radiator. NONE of the air ingested by a CAI has been heated beyond ambient. This certainly affects power. I can make no judgement regarding throttle response.
 
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