Whosurdaddy

I haven't found any reference to a potential aero issue with the rear spoiler on 997.2's. Doesn't it make sense that pulling air into the intake directly from the top of this point is in conflict with its mission to produce downforce? I haven't taken delivery of mine yet, nor had one on track enough to know - but it would seem that these things have a need of a bit of rear downforce.

So, why not install a carbon or silicon tube on the MAS and direct it downward behind the rear bumper? Install a filter at the end and you're done. It would seem that if you were getting rid of the 3rd muffler anyway, that there'd be room back there.

Thoughts on this from the track community?

911SLOW

The 997 Carrera series (without aero kits) don't produce downforce.

For example, in a C2S, the front has 20kg of lift and the rear has 7kg with the spoiler deployed * numbers come from Manthey's aero tunnel tests.

(Note that the 991 is the first one that is zeroed by the factory when fitted with the lowered sport suspension)

Downforce is not in the nature of these models.

Newer GT2s/ GT3s on the other hand are better.


Trying to answer your question, closing the air ducts wouldn't add any significant amount of downforce and would actually disrupt the aero balance, the engine wouldn't be cooled properly and finally you would lose any hi speed ramair effects from having the intake's opening in pressurized position thus negatively affecting power.

J richard

The location in the deck provides a high pressure inlet source, basically a ram air effect. The engine can only ingest a small percentage of the air, not enough to affect downforce most of which is from the wing not the deck. Picking it up below the bumper is a low or negative pressure area, not to mention dirty and hot, not the kind of source you want to feed the engine. Additional intake length and filter restrictions would just reduce engine power.

Whosurdaddy

Yeah, these comments make sense to me. Since almost no street cars actually produce downforce, I suppose the rear spoiler only serves to reduce lift - otherwise why would they bother to put such a nasty looking spoiler on the back.