je ne vais pas vous dire comment je suis tombé dessus (mode tuning de mon tank)
Apparemment il y aurait moyen d'insonoriser l'admission un chti coup en plus
That empty piece of plastic is called a Helmholtz resonator. Really. And it's just empty. Actually not: It's full of air. It's attached to the ducting between your air cleaner and the intake manifold. And although it looks like it can't have any real purpose, it does. It's there to reduce the noise your engine intake duct makes. Huh? It has an interior volume with a very specific resonant frequency, like an organ pipe. Pressure pulses traveling back and forth in the duct have a resonant frequency as well. A pressure pulse whipping past the entrance to the resonator (at the speed of sound) partially enters its cavity. The pulse then bounces off the far end of the resonator, and returns back to the duct a very short time later. By now the pressure pulse has traveled a half-wavelength farther along the duct. The pressure pulse re-entering will cancel out at least part of the negative pulse at that point. The net result is reduced noise, at least at or near the resonant frequency of the resonator. Many car manufacturers use this technique to reduce intake-tract noise. Some vehicles have several of these devices in different places along the duct.
Why do you care? This device should have no effect whatsoever on the performance of your engine, regardless of what your parts manager claims. However, the duct is supposed to be pulling clean air from the air cleaner into your engine. Obviously, the damaged resonator would allow unfiltered air into the works, which would be a Bad Thing. Patch the resonator if there's anything left, or remove it and cover the hole. How? Duct tape won't last very long at all in the heat underhood. I'd try a piece of sheet aluminum and some high-temperature RTV silicone. Be sure to use low-volatility silicone rated for engine-gasket use. It should say "safe for O2 sensors" on the label. Check the rest of the duct for leaks as well, seeing as how you already know there's damage from the fire.
Voilà...
« le problème des citations sur internet c'est qu'il est très difficile de voir si elles sont authentiques »
Napoléon Bonaparte
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Nan nan, la chicane se met dans le flux et donc effectivement bride, le résonateur se met en dérivation et donc n'a pas d'action indésirable voire même pourrait dans certains cas favoriser un écoulement plus régulier et donc plus efficace et donc faire un petit gain de puissance. Et mieux, sur les moteurs 2T, le résonateur est utilisé comme une réserve de mélange sous pression. En effet, le principe des lumières fait que quand le piston remonte, il repousse un peu de mélange dans le conduit d'admission, ce mélange sous pression est stockable dans un résonateur bien dimensionné qui le restitue au cycle suivant. Et calculant la fréquence du résonateur avec le régime de Pmax, on gagne de la puissance maxi. Sinon, on fait un petit pic de puissance sur la courbe.
Ca doit bien peser 500gr un bout de plastique comme ça !
Tu annules le gain des upgrades carbone, c'est pas bon
Et puis c'est sympa le bruit d'aspi d'une admission non ?
Ex 1600K, ex R300, ex SVR200, ex Elise S, Exige V6 Roadster
(mode tuning de mon tank)
