par ghostfire » Mar 29 Déc 2015 22:48
Quand on lit les explications sur le forum UK ça ne donne pas trop envie d'en poser une :
You may not notice any difference, you may notice rough running.
Either way, you WILL have overfuelling.
This can lead to a breakdown of any cats fitted, borewash, diluted oil, excess upper cylinder and valve stem wear, even exhaust valve and manifold damage.
None of which will be apparent until your engine lets go.....if it does. You could be lucky.
But this is what you have to ask yourself, do you FEEL lucky?
And all this for a silly chavvy noise.........
Et ce que je savais déjà, quand j'avais ma S14a :
The Subaru system on inlet relies on a MAFmeter to measure the mass of incoming air after the filter. That air is then compressed by the turbo and the correct amount of fuel added.
Now, if you lift off the throttle suddenly, the excess pressure in the manifold is dealt with by the Dump Valve.
In a recirculating valve, the air is dumped back into the inlet, no longer under pressure and, mixed with the fuel that was measured for it, burns as normal.
However, if you use a VTA dumpvalve, the air is dumped to atmosphere, "lost" to the engine, so to speak. The FUEL however, which was measure for that air, is still in the system, and enters the cylinders with insufficient air, making the rich mixture.