I just took off my flap off of my JCW 06 MCS intake and holy crap that is at least 3x-5x louder depending on if you are near 3000 rpm to 6000 rpm!

the supercharger whine is so much more pronounced and when you get to about 5-6000 rpm and then release the gas, it sounds like a turbo when you release the gas, you can hear the last suck in of air into the throttle.

i drove around town for about an hour in 3rd gear so i could keep hearing the whine. wish i would have done the flap removal sooner.

So to all you owners of a JCW MINI's, do yourself a favor and remove your intake flap!!!

 

what's this flap you speak of?
is it inside the airbox?
only JCW have them?

 

yeah it's inside the jcw air intake. unless you purchased the air box for your MCS. it opens up at 4500rpm to let more air in.

 

any sounds clips??? congrats on the mod.

 

no sound clips. i'll see if i can figure out how to do it. but basically, if you hear the whine, multiply it by about 3-5 times. it's just awesome. I do have a mic and a laptop sooooooo i may be able to do it. i'd go and try it now but i'm on my second pint so i think that would be bad to go driving in the rain.

 

How loud or whats the sound like compared to the Alta? Louder? Same?

BTW, removing the flap gives you the same JCW CAI as the Race Version they sell at JCW Motorsports in the UK, and its what some of the MINI Challenge drivers use.

 

I'm going on the other side of the fence with this, not trying to discourage anyone wanting to try... (fyi, I've got a stock '06 Cooper S with JCW airbox - that's it).

I did try removing the flap after about 2 months, then set it back to stock. The louder intake sound is nice at first (yes supercharger whine and the semi-obtrusive part throttle "whistle" is there). I just found that the extra noise gets in my way with my driving style. So, I put the flap back to stock. I prefer the throttle response when matching revs on downshifting at around 2,000-3,000 rpms and the exhaust note is more pronounced when blipping the throttle. I really didn't feel any improvements in performance, but who am I to know, I always drive the posted speed limit .

This is only my opinion and may not fit your needs. Tune accordingly.

 

I have this mod and the level of noise did not increase that much; I wouldn't use the term AWESOME or 3x-5x louder. The noise starts sooner and is slightly louder without getting obnoxious...

 

I think it is smoother!

 

I also swithched to a Mini Madness air filter!

 

I don't know if my sound changed because of the flap removal or because of the MINI Madness air filter. I have a Miltek exhaust!

 

how can you say it's not louder? It so much louder with the flap gone if you take off or I'd you just step on the gas just a little bit. If you slam the gas, it is 3-5 times louder. I barely heard my whine with the flap in. In 6th gear, I hit the gas and hear it just sucking that air in.

Performance? Nahhh just a coolness factor. I'm sure with the more air the throttle response may be better but who knows.

I can't comment on alta or any other CAI because I have not been in a mini with an aftermarket CAI but I'm sure the aftermarket ones are just the same if not louder on how they are made.

It is basically the same as the motorsport version. The motorsport ones don't have the vacuum pump that opens and close the flap. Only difference if you take the flap out.

One last note, you hear it a bit if you drive normally but if you get it, you hear it a bunch and I'm going to be wasting some gas playing.

 

BeOSKid
I have a feeling that if you think that it is 3-5 times louder with the flap removed then something may have been wrong with your flap opening in the first place. Think about it, once the flap has been opened by the mechanical means you have the same thing. The only difference I noticed with mine removed was that the supercharger wine started about 1000/1500 RPM'S sooner but it was not any louder. Steve

 

exactly...

 

What he said. If it were 3 to 5 times louder, you couldnt be hearing anything in the car. That would be an enormous difference. With the flap off, it should be the EXACT same sound as above 4500 with the flap ... which some think is pretty annoying. You have defeated the whole PURPOSE of a JCW CAI. If you want a loud CAI, just remove the JCW box and add an Alta.

If you got a JCW, the JCW catback is quieter than stock. It would be better to dump the catback if you want some noise pollution, and get a Borla Race .... add some HP. ...

 

not quite, most of us don't think the supercharger noise is annoying so getting it sooner is fine... so instead of getting an Alta removing the flap helps just enough to get a good compromise...

 

I think you missed the point. A JCW is "supposed" to be the "refined" car ... not the boy racers wannabes. It doesn't change the HP. Go to the MINI site and listen to Michael Cooper as he explains why the exhaust is so quiet ... he didn't WANT a loud car. That is also why the flaps exist.

So by defeating these features, you have defeated the purpose of the JCW (and its expensive cost). In that case, IMO, it would have been much cheaper to just go aftermarket. But, to each their own

 

did you guys miss the part where i said "when you get on it?" then it's 3 times louder. not normal driving but when you get on it. reread my last post. i said when you get on it. normal driving it's just a tad bit more noticable.

 

no didn't miss the point and most of us realize that removing the flap didn't add any hp. some of us are not attached to Michael Coopers original intend or how his parts are suppose to work. geez man just let us enjoy this simple mod, it saved me from buying something else.

 

i didn't say any thing about adding hp. just saying when you step on the gas hard, it's louder.

that's it.

 

I can not hear my SC over the noisy dam Gator Back belt untill I get to about 3500

 

This may be slightly off topic, but I just got my MCS JCW and I noticed that the exhaust makes gurgling noises usually when i slow down...like its farting or popping...like putputputput....is that normal??!!!

And, regarding the flap removal...how do you do it? is it obvious when you open up the intake box?

 

That's the infamous "burble" - completely normal.

 

yep totally normal.

want to hear it some more? get a resonatorectomy. wanna talk pops? thing is loud but really cool. it makes the exhaust sound like it should, just loud enough to hear it. of course, the pops are like pop guns.

 

Anyway, I have done the JCW flap removal and took it a step further by removing the vacuum "pot" inside (don't forget to plug them afterwards) and the plug in the bottom half of the box near the firewall. It does make a difference in sound but it is not obnoxious...but then I like the whine of the supercharger.