Montreal Subaru Club

dunlop a écrit :

Mais si t'a un WRX, j'en metterat même pas...

PsychoPat a écrit :

dunlop a écrit :

Mais si t'a un WRX, j'en metterat même pas...

Explique ?

dadydan a écrit :J'ai ce modèle de CAI fabriqué par INJEN. Le filtre est localisé dans l'aile et je trouve ca un peu pas mal ordinaire; surtout pour le changer...
http://www.injen.com/new_layout/product ... D1200P.jpg

J'aimerais pas mal mieux ce modele : http://www.injen.com/new_layout/product ... S1200P.JPG
Quelqu'un a déja modifié le modèle dont le filtre est dans l'aile de facon a installer le filtre dans le compartiment moteur comme sur le deuxième modèle ????

Hello,

Ooh ooh, can I answer this one? No, don't twist my arm. Don't force me to. Okay, I will.

On the dyno, the majority of the increase in power that we saw from aftermarket intakes came from the change in air fuel ratio. The stock MAF is calibrated to account for the way the air flows through the stock intake. Change the intake (notice the MAF is located right after a 90 degree bend, and think about how that would cause the air to flow - higher pressure on the outside of the bend and lower on the inside) and you change the pattern of air flow. The given amount of air passing through the MAF is now not correlated in the same way to the amount of air entering the engine. The MAF reading is incorrect.

So, with a stock ECU, since more air gets in than the MAF reads, the car runs less rich, which creates power.

Now, once you tune the car for the intake and you correct the A/F ratio - ie, you make it the same as you would have done for a car that didn't have an intake, you eliminate that source of extra power. Now the only power difference will stem from the amount of restriction caused by the intake.

What we also found, while I was at Vishnu, is that at low horsepower levels, like the Stage Zero level, the amount of air flowing through the intake is within the efficient capacity of the stock intake. In other words, at 227 flywheel hp, there is no significant resistance to flow in the intake. Providing a better flowing intake will do nothing for you.

At that time, we discovered that as you approach 300 hp (roughly), you start to see some restriction being caused by the intake. I can't remember exactly, but I think we found that you could tune the car with a free-flowing intake to make about 4 more hp than a car with a stock intake and a stock paper filter (which flowed better than a K&N drop-in, though I am not sure the difference was statistically significant).

So what Shiv is saying is that (I think) in a lower Stage package, there is no benefit to the intake because the stock one is not restrictive. If you're tuning the A/F ratio correctly, that means there is thus no benefit to be gained from the intake.

Once you get more horsepower, though, the intake can prove effective if your tuner takes advantage of it.

This above problem is also why (I think) Cobb only tunes for their intake. To properly map an intake takes some time and careful consideration. As Shiv said, it's an extra hour of dyno time to account for an intake. Well, the intakes magnify other car-to-car variances, so if you're not sufficiently intimately familiar with a particular intake and how it works with other mods, you need to spend that dyno time with each particular set of mods.

Joel

COM@ a écrit :Pour la garantie, est-ce que qqun a deja eu des problèmes avec un CAI?

Swatch a écrit : À partir que t'es plus stock, la garantie part en vacance