holes in airbox - any idea why they are there? (996 3.4 C2)

[MrJingles705]

Was taking out my airbox for the first time (wanted to get a clear look ar the belt and pulleys) and noticed that there were holes on the bottom right hand side, directly below the part of the filter that lines up with the intake into the MAF.

Why are they there?

Noticed after i put it back together that it seems to draw air from this area in preference to the intake snorkel on the boot lid ... That can't be a good thing can it? Drawing (relatively) hot engine bay air rather than cold external air?

Not drain holes as there is already a single (larger) hole moulded in at the lowest point.

Guessing it's there for induction noise?

Has anyone tried taping it off to force air to come from the 'proper' feed? Seems that the snorkel diameter would be large enough to flow air to the throttlebody itself without this.

Searched for ages, can't seem to find anything or anyone mentioning this ... Can't just be me that noticed!

(Hoping i'm not being thick here)

[Orangecurry]

Induction noise. On the 993 the drilled airbox is part of the 'Motorsound package'.

[ashley95]

Yep purely for noise i believe.
'boy racers' i believe sometimes do the same on their Corsa's and Fiesta's

[MrJingles705]

Cheers gents.

So ... Taping it off to get a better air feed ...?anyone done it, any downsides at all?

[Pope]

The OE sound package had the holes and a chrome intake sleeve on the airbox, along with larger chrome tail pipes. The holes induce a resonance in the intake that gives a boost to intake noise - doesn't detract from performance and sounds nice inside the car.

Guarantee if you tape it up you'll think the car has lost power and sounds dull.....

[MrJingles705]

Ok ... Well, decided to test

Taping it off - slight induction noise reduction, not as much as i expected. Power didn't go down so definately no choking off (enough air is flowing) but no noticable extracpower either except a slight (very slight!) improvement when the car is running mega hot (as in, 98 deg plus) - which took some doing in this weather!

That could have been placebo effect i admit, but i'm reasonably confident there was at least something there.

So - meh really.