[roadkillrob]

It has been my experience in the past that just sticking a cone filter under the hood sucking hot air actually reduces performance in most cases. The 335i setup seems to stick the filters into a pocket beside the engine with no real airflow to them, so it stands to reason that they are sucking much hotter air than the airbox or a proper cold air setup would get.

My question is, does this affect performance on the 335 or because it is a turbo car, that the intake air temp doesn't really make much of a difference as it is heated up so much going through the turbos and the end result in the intake manifold is net net the same. Or does the increase in available airflow help enough that the hotter air makes no difference.

Just trying to figure out if it is really worth doing performance wise, or will it end up being more cosmetic?

Rob

[scottp999]

You have it. The intake air is cooled by the inter-cooler before going into the manifold. So on a Forced Injection car w/ Intercooler, air intake temp is not as vital as on an NA car.

People have actually checked the post inter-cooler temps and the difference is negligible.

Not everyone agrees, so opinions will vary.

[mmmotornutz]

If you look into other modified boosted vehicles from Audis to Volkswagens (A-Z), the air filters are not enclosed in a box. Reason being, heatsoak is not an issue with boosted vehicles due to the IC. CAIs for boosted vehicles is just a sales gimmick, sales pitch a money maker.

[roadkillrob]

cool - thanks for the resoponses - I may have to waste some more of my money on the dual cone mod!

[longodj]

It's cosmetic, but a damn good cosmetic mod at that. The sound is addicting as hell!

[normtrum]

Originally Posted by longodj

It's cosmetic, but a damn good cosmetic mod at that. The sound is addicting as hell!

True....however it becomes quite a bit more when you're over 350 hp. According to the experts anyways.

I like the way it looks too....and I really love the way it sounds. Oh, and I'm at 330 hp, so I'm not seeing the optimal effects either. Yet.

[StarrDlux]

actually the air filter (and box) for my 1.8T (stage 1+) has zero gain over stock paper by any means possible. the same size airbox and filter was used on the 2.7TT (including chipped) and only showed restrictions when folks were cranking the boost up on the V-6 2.7TT.

if you are going to do a CAI at least place it in a CAI area where you have done pressure measurements to ensure airflow at speed is decent. so far i've only seen Hot air intakes on the 335i. it seems like the CAI should come right off the turbos and go somewhere cool.

my concern is really when you sitting in traffic your heatsoaking; i believe it works great when you are moving but you then have a hot motor when you get moving that is punishment. the stock airbox seems to draw only cool air from the front of the grill area.

someone route the outside ambient air temp sensor into the :
1. stock airbox (filter side so it doesn't get sucked in)
2. custom twin air filter, attach it to bottom;side;top

go sit in traffic and tell me what you see on the ambient. probably 145+ on those dual open air filters.

i'd bet its about 20F less with the stock air box.

i'd try it but i wouldn't want to ruin my warranty to find out i'm sucking hot air in the 15 minutes of traffic that seems to happen every day.