After installing the HAI, I too can hear a metallic buzz, usually, but not always under some sort of load. I,ve had the HAI on around 3 weeks now
and don't find anything loose either. I think it's noise coming through the throttle body.

 

Thanks! Glad to know it's not just me!

I have driven alongside buildings with my windows down in order to hear it clearer. I can hear the throttle body open up but then I still hear the buzzing only around 2500 rpm.

Would some lubricant (WD-40) on the throttle body help? ....No, I haven't done it already Or is it too much air?

 

It's probably due to some resonation in the intake system, now that we've eliminated the intake resonator....

--
Cheese

 

you are very knowledgeable oh cheesemeister!

shareth with me thou sage advice. What shall I attempt to appease the reasonation complication?...

seriously,...any ideas? It's bugging me! I listen for it through every gear! I will turn down the stereo to see if it is still there! ....If the consensus is that it is non-detrimental to the throttle body or any other part of the system then I can leave it be. However, I would like to exhaust all possibilities...

thanks for your input.

 

Its probably related to the length of the intake path. By changing the path length, you can change the resonance frequency. Sort of the same principal as dual runner intake manifolds.

If it really bugs you, I guess you could try either a different shaped filter or maybe sliding the filter up or down on the throttle body's lip if thats possible. Do you have the straight one that I (and now andy) have or the angled one? Switching from one to the other might be enough to eliminate it (or atleast shift it to a different rpm ).

The other possibility is that its something that used to be secured and now isnt... like the PCV hose slapping your cylinder head or the battery cable hitting something now that you've removed the intake box top... Take a look around and make everything is snug.

--
Cheese

 

I have the same problem with the Alta CAI :-\

 

I'm using the angled filter, with a breather filter on the PCV (?) hose and have not noticed any buzzing.

 

I used the 1550 with a breather on the end of the line. I'll try securing the breather off the engine...it does lay against it...

thanks for the feedback!

 

Just to mention here. I have had no further problems with the 'choppy idle' syndrome since installing the HAI. Interesting side benefit.

 

I still have it....

 

Me too. I still get the occasional "choppy idle" even with the HAI.

 

Thanks for the feedback guys. I thought I was on to something there, but I guess not. I'll have to see if it happens to me again.

 

I should be receiving my K&N RU-1550 today and I had a quick question about the oil breather filter that I'll need to install. Are the filters one-size-fits-all or do I need to know the diameter of the hose that I'll be attaching it to?

Thanks

 

The hose connecting the valve cover to the intake is 1/2" ID, 3/4" OD. You can find it at any auto parts store as "heater hose". You'll need to make sure your breather fits into that.

 

2000 mile update....

i love my HAI!

the sound of the throttle body and supercharger are amazing.

it feels faster even though i havent dynoed it.

this was the perfect solution while waiting for the M7 CAI.

this is a pic of the old install, now its a hell of a lot cleaner.

no messy wires and such.

 

Installed my HAI and breather today. Seems to be quite secure. I used the 1550 and had no trouble getting it to stay on the TB.

I do however hear the buzzing noise people have talked about. I can hear the metallic sucking noise which I think is the butterfly valve opening, but I also hear some buzzing at various times. It doesn't seem to be at any particular RPM... oh well... if you hit it hard enough you will only be able to hear the super charger anyway...

Would it be possible that the buzzing is the filter vibrating against the hood liner? Mine touches the liner and has already made a dent it in even though it has only been on for a few hours. The filter could be transmitting vibrations from the engine into the liner and it might be buzzing. Does anyone without a liner have the buzzing noise?

Oh yeah... it sounds great even though I can't really feel all that much of a difference in power... of course I just got the pulley about two weeks ago and don't have much of a mental baseline.

 

I am finally going to put on the HAI. Before I get my RU 1550 from the local chain parts store (nothing wrong with them) or just anyone online, I was wondering if any NAM sponsors sell it. I searched this thread and have read it time and again over the past few weeks, but can't find mention. I would like to support our site sponsors if I can. :smile:
Thanks,

 

Thanks a lot everyone. I was looking for information on an infant seat that will fit in my 02 MCS, and now I have to explain to the wife why I just ordered an air-filter!

Anyway, I'm real cheap, and I can't resist this one....

 

Is this thing overkill? Supercharged or not, we're only talking about 1600cc.

That looks like one honking huge air cleaner. Looks more suited to some huge earthmover than the smallest car sold in America. I don't know anything at all about these things, but I would assume there must be some sort of formula involving filter material and surface area and cfm relative to engine displacement and max rpm or something like that.

I've read the whole darn thread from start to finish (I've got time on my hands - my car is still on the Atlantic) and I've seen some comments about smaller filters. The response to this has usually been that the pressure against the hood liner helps hold the filter in place. But I wonder about the wisdom of that - isn't that pressure going to put some unwanted stress on the throttle body as the engine shakes? (How much does the engine on an MCS shake, anyway?)

 

Well, I just did the HAI. I'd ordered the filter a few nights ago (my wife was very understanding). I read the Alta instalation how to and comments. And went at it.

I decided to leave the base of the airbox in place (I live in CA, a state with inspections with smog) so I can go back to proper. It took less than 10 min to do, the hardest part is deciding where to tighten the K&N clamp.

To Lombard Street: Some comments on flow. A restriction is a restriction. As the filter gets bigger, the resulting improvement drops, but never hits zero. But practically, this thing may be at a size beyond what's smallest to do a practically identical job. But then the extra area goes to longevity, or tolerance to crap build up. but after all than, it does look pretty big.

I'm pretty sure a horn or something to smooth flow would improve the package. There seems to be a bit of room (the rubber has some "slop" before the clamp is tight), anyone good with sheetmetal?

But for under $40 delivered (2 days for me), and likely good as performance as something 4-6 times as expensive, I just couldn't resist. I tugged on mine after installation, and it seems pretty secure.

I drove it around the block and didn't hear much difference with the windows up, with 'em down, I hear some whine. But this was just a mile drive. The car is getting castrated Friday morning (going to a one-ball exhaust) so any impression of just the aircleaner will be short and (I hope) sweet.

Matt

 

There are two schools of thought on intake design. One is a tuned length intake that is optimized for flow over a given (limited) powerband. The other is large plenum directly above the throttle plates that has a large ammount of filtered air available immediately. Both have their applications. Long tube intakes are generally seen on Hondas and the like where they're tuning for the narrow range of the VTEC system. Large round aircleaners are typical on V8 musclecars. The reason for the large filter on the HAI is I'm a believer that situation 2 is ideal for this application.

The original HAI design incorporated a properly designed post filter airhorn and some pre filter ducting but the horn ended up too big to fit due to space constraints and I gave up on the ducting when I no longer owned the car.

The majority of the MINI designs right now aren't following either rules and I think thats why their performance are all so-so. The only ones playing by the rules (that I'm aware of) are the HAI and the K&N Typhoon with its tuned length tube.

 

Hi all,
This thing really works! Not huge power gains, but with the MTH and the HAI, I'm actually using the 1-2.5k rmp range and not getting scared! Anyway, I'm a happy camper for $38 bucks!

Matt

 

try a one-ball to get the most out of it - I did & I'm a happy camper :smile:

 

I'm getting that done tomorrow morning, 9:00 am!

Matt

 

great for you matt - best dual mod for under $100

anyone have problems with their HAI popping off - I had to reseat mine today - it was off the throttle body a tab - so it was sucking some air in directly.

great for you matt

any thoughts?