I just installed the Alta intake on a stock MCS. The performance increase is small but clearly present. I am noticing a high pitched whistle coming from the engine when the throttle is just at the "load" point. It sounds like air passing through a confined area and is quite seperate from the "whoosh" sound on take-off. This sound occurs at highway speeds when the throttle is pressed a small amount to correct the vehicle's speed. ie. it is annoying to run 70 MPH and lightly press the petal and hear this dog whislte noise. Any ideas?

 

I have the Madness intake and it does the same thing. Took it in and the MINI service tech said not much you can do about it. It's a small air leak in the throttle body.
Disclaimer - I am by NO means technical and he could just be blowing smoke up my exahaust. If other more knowledgible folks on this site could lend some other more informed opinions I'm all for it cause I'd rather come off looking like an idiot and fix the whistle than attempt to mislead others by having people think I have a vast wealth of vehicle knowledge.

 

It sounds like you're hearing more intake and supercharger noise. That's normal.

 

Its different than the intake "whoosh" and the supercharger "whine". It sounds like a dog whistle.

 

Check the bottom of the bonnet. The new intake should be making a slight impression on the material where it makes contact. Maybe there is an area that isn't touching?

 

DiD - I'll have to agree with Rafthos - It's definitely not supercharger whine or airbox noise. It's VERY high pitched and only happens at certain "load" conditions. It's more high pitched than even say a tea kettle.

 

yea, just about every MCS I've driven has this subtle whistle, mostly on very light acceleration- regardless of modification level (yes, even stock). While not annoying, it's certainly strange.

 

I'll check that as soon as I get home, thanks :smile:

 

I haven't heard a high pitched wistle with my MINI.

I'm not sure I could hear it if I wanted to though

 

Randy just installed a bunch of these intakes here this weekend. He said that whistle is "normal" on the Alta system especially as you also remove the back wall of the air box. What you hear is more of the throttle noise. He is on a flight home now, but he can explain it quite well.

 

I have the Pilo MCS intake with the airbox mod and the whistle is very noticable. I used to have other performance cars with cowl induction systems and this is NORMAL. What we are hearing is the initial stream of air whistling past the throttle body butterfly. As the the butterfly opens the whistle is replaced by that wonderful supercharger whine. From whistle to whine then whooosh.
Ain't it COOL ?

_________________

 

I have the Alta, and the whistle. Asked my mechanic (not MINI) about it. He said that the throttle body always makes that noise when open just right. (it just happens to be when not accelerating or slowing down, when keeping the constant speed). The reason you didn't hear it before is because of all the plastik and paths in the stock intake. It muffles a lot of things down, i.e. supercharger whine...

 

Thanks for the info. I was afraid it was the throttlebody butterfly. Maybe the pitch will change after a pully upgrade. Till then i'll just increase the volume on the tunes when hwy drivin.

 

>>Thanks for the info. I was afraid it was the throttlebody butterfly. Maybe the pitch will change after a pully upgrade. Till then i'll just increase the volume on the tunes when hwy drivin.

Rafthos,

I have it as well and you've describe it pretty well. Mine whistles at ~3k steady-state throttle, and was only noticeable after replacing the intake.

I'm not concerned but if you ever track it to its source let us know.

ps: Best intake noise? A pair of flat-slides on a Duc monster I rode recently. Off-throttle it makes a little chirping sound that's a right laugh. The back on the gas and the termis sing!

 

Seems we're all in good company on this one .........Good to know it's not just me

 

I think the Alta Intake sounds cooool

 

>>I think the Alta Intake sounds cooool

Oh, no doubt. I still wouldn't go back to stock.

 

Hehehe! I just installed my ALTA intake today!

Yup, I heard the whistling sound. On my MCS, the noise comes right when I punch or tap the gas pedal.

Its a cool noise though. It sounds just like those high pitched "whistling" blow off valves - except you are pressing on the gas pedal to make the noise .. not the clutch.

I have been doing my research and everybody says that you can hear the supercharger more clearly after adding the intake... GEEZ! What an understatement....

The supercharger is super loud now! I love it!

ALTA rules!

Got my pulley sitting on the table... waiting to install it next week.

I cant wait =)

 

You might want to check out my post. I didn't notice yours or I would have put it here.

https://www.northamericanmotoring.co...ic=18553&0