If charcoal filter removal indeed contributes to most of 17hp (~5%) gain, which is not impossible, this Dinan CAI is a total rip off.

Anybody get dyno data for charcoal filter removal ?

 

That was easy. Took just 5 minutes. Did not remove sensor - able to rotate the cover 90 degrees and pry out the filter. As katheikia mentioned (in this post) there are no clips for this filter in the 550 - it just sort of snaps out.

Went out for a 30 minute test spin. Yes, you can notice it. It settles into idle smoother. Throttle response is right-now, hold-on-tight, help-me-Jesus, full-on-DSC-flashing quick. Where was this before?

Overall you can tell it is breathing easier and more fully ... everything is smoother, quicker, and has more snap to it.

Frankly, the 550 did not need any help ... so now this thing really scares me.

This is a wonderful find. Best 5 minutes you will ever spend on your E60.

Thanks stream, lomag, and the m5board.

 

I removed it and really I don't notice any performance gains. There is no way that little piece of paper is restricting air flow enough to retard engine performance, sorry guys. Think about it-- the rate limiting step to air flow is the air filter which is substantially thicker than the charcoal filter. Until I see a before and after dyno report I don't believe it makes one difference.

 

The Dinan is supposed to have DUAL Air Flow Intakes (2), which would account for larger air-flow than our single Intake. More air would account for more power.

For those who don't know how Dinan does their Dyno, Dinan uses a super high powered fan to push air into the intake box, which boosts their HP gains, beyond any other Dyno machines. They have been criticized for the numbers that are put onto their products as they are unlikely to be seen by the end user. Their products are top notch, but take the HP numbers with that in mind. Will you have gains?? Yes, but will you see their numbers?? Not likely, unless the winds are perfect on the track/highway.

 

I agree. It's so close IMO, that it is hard to say it's true without a dyno run. OTOH, it sure was sweet kicking it. I had not done that for a while.

 

does the EURO spec car have it too? what about 530i engine?

also is not there a risk of some dust getting in to the engine with the less efficient paper based filter?

 

I agree with you! Let's not be drastic now and tell that before it was kinda slouch and boring and now an amaizing super fast car. Even so i bet there is INSIGNIFICANT whp [u]improvement...if there is any.

 

Please see last post on this page for the purpose of charcoal filter: http://www.m5board.com/vbulletin/showthrea...?t=66688&page=3
It's obviously not gonna hurt anything if removed.

On my car, I can see lights through orange air filter but charcoal filter is so thick that I pretty much cannot see lights through. It has to have impact on air flow - common sense.

Sure, only dyno data can be conclusive.

 

The Dinan is supposed to have DUAL Air Flow Intakes (2), which would account for larger air-flow than our single Intake. More air would account for more power.

For those who don't know how Dinan does their Dyno, Dinan uses a super high powered fan to push air into the intake box, which boosts their HP gains, beyond any other Dyno machines. They have been criticized for the numbers that are put onto their products as they are unlikely to be seen by the end user. Their products are top notch, but take the HP numbers with that in mind. Will you have gains?? Yes, but will you see their numbers?? Not likely, unless the winds are perfect on the track/highway.
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Yes, the Dinan CAI does have 2 intakes. I didn't mean to suggest that all they changed was just the airfilter box cover.

As for their high powered fan, I've seen it in their dyno room. As I recall, it's about 4-6 ft in front of the car, I think and it's used to simulate air flow at speeds which is common in any dyno facility. I'm not sure if I understand what you mean about it being used to push air into the intake box. Do you mean that air is funneled directly to the intake box because it looked like it was just aimed at the general frontal area of the car.

 

hmmm i'm going to try this when the car gets back...