I'm trying to find someone with first-hand experience of having the dreaded throttle whistle (sounds like a teakettle at slightly open throttle, NOT supercharger whine, which is good) and switching to a JCW intake with the flap enabled as a solution... full writeup of my malady and testing are on my blog here.

Short version - the throttle itself in some cars emits a loud whistle when partially open at a specific angle... the stock airbox config with the "muffler" chambers on the snorkel help suppress this sound from leaving the car... if your car has the whistle, most CAIs allow it to be heard clearly through the cowl cold air vent... this whistle usually happens at throttle positions that yield the 2500-3500 RPM range.

I'm speculating that the JCW intake with it's flap closed will mostly or entirely suppress this sound - that could even be one reason they engineered the box as they did with the flap closed at lower RPMs... to block that "undesirable noise" (more speculation on my part)... But I'd LOVE to find someone who has actually had the whistle with another CAI, and switched to JCW afterward, to see what their results were... before I shell out the bucks to try it...

So...
If you:
a) switched to a non-JCW CAI, AND
b) had the throttle whistle, AND then
c) switched to a JCW CAI...

Please let me know your experiences...

THANKS!

 

Heard a nearby Alta with the dreaded teakettle at very slight throttle openings, but haven't heard of a solution (though one post suggested using the OE intake tube instead of the sexy Alta red one, may try that and see). It is annoying though, the owner is trying to decide if the silght pwoer bump and inceased whine (both desirable) are offset by the teakettle...

 

^ I think you're gonna get it with the Alta no matter what you do.
There's a post on another thread were the Alta CAI owner was told to do exactly the opposite: try replacing the OE intake tube with the sexy silicone.

Blimey -- hope the JCW does the trick . . . if for no other reason than that I'd consider taking the Dinan CAI off your hands.

 

To get rid of the whistle (Low throttle whistle)on a CAI put back in the rear plastic wall and the whistle disapears. The SC whine is a little less as well but to me is worth the trade off.

 

I have a lot of noise with the ALTA, but it's a sucking noise due to the TB sucking air in...not a whistle at all...hrmm... I do have the VGS mod though.

-Cody

 

If you have a whistle, it WILL whistle with either hose. i've tested this. Makes no significant difference.

 

... except, (1) I have the Dinan - which doesn't remove the cowl wall (though it DOES vent into the cowl)- still whistles, and
(2) putting the wall back in removes the supplemental cold air source that makes a CAI beneficial...

 

I have no whistling with my JCW intake. If you are looking for one Eric at Helix has a great deal on a couple.

 

.... but do you have whistling WITHOUT your JCW intake? Because many cars have NO WHISTLE at all...

 

No my car didn't whistle before so I can't tell you that the JCW cured a whistle. I can tell you it did not cause one for me.

 

Turn up the tunes. Works all the time for me. But then, I can't here that lovely sucking sound.

 

Why is it such a dreaded sound???

It means your engine is breathing very clearly. So what if you hear your throttle body whistle? Perfomance is what you paid for.

Performance first. Comfort Second.

 

That's what I kept telling myself. For about 5,000 miles. But it's like fingernails on a chalkboard. People say what you said - until they hear it - then they say "Geesh - what's wrong with your MINI?!?!"...

 

ya know, I don't mind the Ross Perot ("giant sucking sound")... it's that tiny little whistle at really small throttle openings, like exactly where the throttle is while accelerating gently, or on a slight climb on the interstate, or traveling at just your preferred highway speed... it's like an italicized whistle...

 

Exactamundo. YOU know what I'm talkin bout.

 

Blimey: you really have some serious beef with this whistle don't you?

 

I would shove a Kobe steak in my intake if it would make it stop.

I'm getting a JCW intake - got a bargain and have one waiting for me to pick up... will see what that does - I'm optimistic...

 

 

(dip throttle) whistle fade to whistle (lift throttle) no whistle (dip throttle deeper) whistle to whis-WHINE-SUCKING SOUND-MOVE-WHine-whistle-stop

AAAAAAAAAAGH!!!!!

 

^ that's great . . . but how did you get rid of the "italicized whistle"

 

I turned the car off. It's the only thing that worked.

 

I forgot to test it with the flap down today. I'll try to remember to do it tonight.

If I connect the vacumn line to the intake and route +12V via a switch to the acuator, would I be able to control the flap via the switch? I never got around to testing this, but if someone else has, I'd love to know if it worked.

 

Just for info.... I've got the JCW intake with the flap removed. I hear the Ross Perot whenever I have the gas down, and I also hear the italicized whistle (almost sounds like a tiny ringing sound) at various times. I don't recall hearing either before I had the flap removed, though, so that may be your answer.

What worries me is that I don't hear the s/c whine anymore.

 

Interesting that you're not hearing whine. Do you have a reduction pulley, or stock pulley? I hear plenty of whine with my Dinan - with is basically like the JCW without the flap... Though it's certainly nowhere near as loud as the Alta and other metal-boxed intakes I've heard. The filter may also contribute - The Dinan uses an oiled gauze similar to K&N... the JCW uses thicker paper... but I'm going to use an Amsoil Nanofilter on mine...

 

I'm not sure what's going on. I've got a basically stock JCW car - Milltek catback and Mini Madness gauze filter in the JCW airbox. The pulley is whatever reduction my JCW came with. I used to hear plenty of s/c whine, but I don't anymore. I don't know if the louder intake and exhaust noise is drowning it out or if s*** ain't workin'.

I need to get a recommendation for a shop in the Bay Area (or somewhere else in Nor Cal) that specializes in MINIs, and really knows their stuff. I don't feel that the dealer or this other BMW/MINI shop that I've been going to really are on top of everything.