Airbox intake silencer
 

I have heard that you can take the silencer off the standard air box, does anyone know what the benefits would be, how to do it and if its worth doing?

Cheers.

The only benefit is a bit more noise to be honest, you here some turbo whine and the stock recirc dump valve a little, no real performance change.

Simon

Harvey (Smith - Harvey Performance) tested his classic with and without the intake resonator with a variety of air filters and IIRC he concluded that without it there was a reduction in performance and he observed some erratic AFR or MAF readings. The OE paper air filter also proved to be amongst the best for flow, filtration and performance with little/no advantage in using after-market items, except for their lifetime usage.

Harveys tests were carried out without a remap at the same time and showed the potential risks of haphazard modding.
The MAF response with changing a filter and the silencer needs to be recalibrated with a remap to be safe.

If you want to remove the silencer, then save it until you want to add a number of other mods and a remap, to give the best and safest output.

nick

Thanks for the feedback guys. It would be nice to hear the turbo spool up a bit more, I miss that from my old Renault 5 turbo, a remap is planned hopefully early next year so maybe wait till then. Although it is tempting. If I were to do it is it easy or a pain?

if u want to hear ur turbo spool up get a open neck decat downpipe, makes a massive difference in spool up, much quicker and louder, more power etc.

It's fairly easy to do. Wheel off, arch liner partly off (4-5 clips), ram-air scoop off (2 bolts), pop off the fog trim (remove fog light on WRX (2 bolts) to gain access to one bolt behind the bumper, one bolt in the engine bay next to where the scoop attaches, extract through wheel arch, seal off all holes between the wing and engine bay, then use sponge or rubber hose to make a seal around the air-box to prevent dirty, hot engine bay air getting induced. I opened up the little triangular vent beside the O/S foglight by drilling out a small piece of the foglight mount plate (soft plastic) and a small opening in the undertray to let more air in. DV was perfectly audible, as was spooling. The car appeared to run ever so slightly cooler in traffic after, and spool slightly earlier, but with no measurement of this I cannot verify these effects. I ran it perfectly safely with a JR Racing filter for about 2 years.