R55 AEM (21-721C) Cold Air Intake System
Took the car in for service today and talked to one of the master mechanic there about the CCID-029 code.
He indicated my Magnaflow exhaust and AEM cold air intake in combination may make the system more a bit free flow than the ECU expects in certain situations. He agreed the code was triggered by the high vacuum reading, and if all it took was to clean the filter. Just do that. To me this is no biggie because I detail the engine compartment when hand washing the car so I look at the filter once every week or so.
He said if the code doesn't clear, pop on the stock filter housing and bring it in and let them look at it under the emissions warranty. But he said not to worry about it.
So basically, if you have an issue revert back to stock and see if and it still does it, then bring it in and revert back afterwards.
Again this dealership is not concerned with either the CAI or the exhaust as far a warranty goes. (now an ECU mod MIGHT be another thing)
He indicated my Magnaflow exhaust and AEM cold air intake in combination may make the system more a bit free flow than the ECU expects in certain situations. He agreed the code was triggered by the high vacuum reading, and if all it took was to clean the filter. Just do that. To me this is no biggie because I detail the engine compartment when hand washing the car so I look at the filter once every week or so.
He said if the code doesn't clear, pop on the stock filter housing and bring it in and let them look at it under the emissions warranty. But he said not to worry about it.
So basically, if you have an issue revert back to stock and see if and it still does it, then bring it in and revert back afterwards.
Again this dealership is not concerned with either the CAI or the exhaust as far a warranty goes. (now an ECU mod MIGHT be another thing)
Well my R55 now doesn't hesitate as often as it use to for me. I do feel the difference in terms of performance but not by a lot. I think once I put in the exhaust system and tune it up at a shop I may be able to really tell the difference. Although, I sense the engine is breathing a lot better and when I am on high rev, the engine does sound a little louder. The current exhaust does also sound a little bit better but again its nothing too obvious really I only have the MCS no JCW =/
As for the scoop under the hood, it does get very hot... like by a lot. I have driven it for a while on the expressway and what not and after a "good drive" I tend to check out the scoop underneath since I been reading on the forums about warp and stuff but thus far nothing seems to be melting nor warping.
However, the Heat shield that it comes with gets crazy hot and while it does seem to not be pushing all that hot temperature upward towards the underneath scoop.
I am still working on a little minor project on adding a mesh in replacement to the original plastic vent so that the air flows better as shows on above threads I posted and suggested by one of our community members. I agree it needs more airflow and so temp I took it off for now until I can get that adjusted later on this week or next week. The instructions did suggest to leave it off.
As for the scoop under the hood, it does get very hot... like by a lot. I have driven it for a while on the expressway and what not and after a "good drive" I tend to check out the scoop underneath since I been reading on the forums about warp and stuff but thus far nothing seems to be melting nor warping.
However, the Heat shield that it comes with gets crazy hot and while it does seem to not be pushing all that hot temperature upward towards the underneath scoop.
I am still working on a little minor project on adding a mesh in replacement to the original plastic vent so that the air flows better as shows on above threads I posted and suggested by one of our community members. I agree it needs more airflow and so temp I took it off for now until I can get that adjusted later on this week or next week. The instructions did suggest to leave it off.
Now remember this is subjective i do not have numbers to back it up and I was also expecting a difference to justify the expense. So take the feel with a grain of salt.
I did notice the combination of the two did bump the avg MPG about 1.5 to 2.0 MPG overall. That was the first 1000 AFTER I stopped romping on it to hear the exhaust sound.
Now one thing this CAI does have over others is the ductwork and scoop.
I honestly do not see why people buy a CAI without a scoop and have it suck 140 degree air from INSIDE the engine compartment. The ductwork on this CAI will at least give you ambient temperature (or close to it) from the OUTSIDE. On a 100 degree day that is a substantial difference in induction charge temperature. On a turbo motor this is critical.
Now AEM did mention in the notes to remove the CAI in the winter. I have driven in 20 degree weather and snowing with no issues. But rather than remove it I would simply fabricate a metal blank to replace the top of the airbox and seal it off that way. After all it it just a 6x11 plate. That seems to be a lot easier and forces the CAI to use the factory ductwork at that point. It would be nice if AEM made such a plate but they do not.
I purchase mine through 4x4autworks.com. I searched the site for 21-721C and there are two links. One for $397.99 which is pretty much normal price, and another that says "add to cart to see price". That one is $297.99 and its the same part number. I chose that expecting the order to get rejected (too good to be true) however it went through. Bam! $100 saved. I just checked and the link it still there and should work just fine.
Thanks,
Mike
It is connected to the stock plumbing, BUT the scoop feeds directly into the top of the airbox. Close off the feed from the scoop and you basically have the factory plumbing intact.
Of course the air is going to take the path of least resistance and use the scoop which is outside ambient temp. I would imagine a tiny bit does feed into the engine from the factory plumbing but it should be minimal.
I ***-u-me in northern climates during the winter the scoop could funnel the air and moisture in and form ice along the pathway in freeing temps. It could then melt and drip into the airbox and on to the filter. How the Mass Air Flow sensor handles that is probably not good.
Driving rain does not seem to be that much of an issue for me....yet
However the factory plumbing would not have this issue in either rain or freezing precipitation.
I thought the factory tube ran all the way up next to the headlight? Mine does. Would figure it could be succeptable to that as well.
I know one of the ram air intakes has drain holes before the filter box for water. Maybe drilling a few holes there couldn't hurt?
I know one of the ram air intakes has drain holes before the filter box for water. Maybe drilling a few holes there couldn't hurt?
The holes would work depending how they were to be placed, but be careful of what they would drain on. (H20 and spark plug coils probably don't go well together)
I eventually hope to tap into the OBDII port and actually measure the induction temperature with the CAI open and blocked off. It would be interesting to see if there is a difference (might not be much), but part of the CAI is to reduce restriction as well. The additional pathway from the scoop easily accomplishes that task.
That is why I question the wisdom of simply replacing the airbox with just an open element filter. Yes, you get reduced restriction, but at the same time you are now sucking air into the engine that may be up to 50 degrees warmer than ambient. How big is that trade off?
Now I might be talking a bit out of my element here but I will try anyway.
You need to keep the induction temp as low as possible
Here is what I am thinking:
Two cars with modified induction and one without.
Ambient temp of 85 degrees
Turbo induced heat increase of 50 degrees to induction charge
Engine bay temp of 135 degrees
Car 1: Stock using restrictive airbox
Air intake temp at Mass Airflow Sensor 135 degrees
Car 2: Open element low restriction filter sitting on top of engine drawing in heat from engine bay;
Air intake temp at Mass Airflow sensor 185 degrees
Car 3: Open element low restriction filter with outside at access (scoop)
Air temp at Mass Airflow sensor 135 degrees
Cars 1 & 3 have lower intake temps will all things being equal.
Cars 2 & 3 have less restriction
Car 3 has both low restriction and lower intake temp
Theoretically Car 3 has the best of both worlds.
Of course this is just my hypothesis.
The point is get ahead of the game and lower the intake restriction and the temp as much as you can, because you probably won't be able to do too much about the heat transfer from the turbo itself.
You got me thinking so I did a little reading. An extensive UK comparison of intercoolers from a Subaru magazine found that intake temperature correlated to almost 1HP per 1 degree Celsius on their turbo motors. Using my figures from above that comes out to almost 10 HP lost just due to excessive heat.
So playing devils advocate here, assume you really lose only half of that..... well, you still left 5 HP on the table due to heat.
BTW AEM estimates a 6hp increase for the Mini intake. Given that, I would assume a good portion of the increase is due to a lower intake induction temp rather than reduced restriction in the factory ductwork.
Just something to think about.
Last edited by NTX Clubman; Dec 7, 2014 at 07:12 PM.
Here is an update on how things are going on the cut out of the inter plastic scoop vent.
It's not done yet , we just got half of it done.
The other half still needs work. Then after I will add the Mesh as suggested by NTX Clubman.
Once it's finished I will install it and post back.
It's not done yet , we just got half of it done.
The other half still needs work. Then after I will add the Mesh as suggested by NTX Clubman.
Once it's finished I will install it and post back.
Obviously this is not a turbo charged Mini, but I have a Harley, and I changed out the exhaust for a loud one. I got loud with no power gain. I wanted it to breathe better and put in a high flow filter. I got a small increase in power, but it still felt stifled. Then I changed the ECU mapping and got a significant feeling of extra power - perhaps as high as 15% maybe IMO.
So then, can a breather alone give more power to the Mini? Or is it the case where the exhaust also needs to be modified, along with the mapping? I'm thinking that's where and when the real performance gain will be felt.
I'm no mechanic, just the clown at the wheel.
Ditto, ditto, ditto. Obviously this is not a turbo charged Mini, but I have a Harley, and I changed out the exhaust for a loud one. I got loud with no power gain. I wanted it to breathe better and put in a high flow filter. I got a small increase in power, but it still felt stifled. Then I changed the ECU mapping and got a significant feeling of extra power - perhaps as high as 15% maybe IMO. So then, can a breather alone give more power to the Mini? Or is it the case where the exhaust also needs to be modified, along with the mapping? I'm thinking that's where and when the real performance gain will be felt. I'm no mechanic, just the clown at the wheel.
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Exhaust might be similar but I still can see compromises being made for a exhaust tone or overall quietness. THAT might result in a decrease of power in stock form.
Combine that with numerous youtube vids out there that seem to back up the intake restriction theory on different makes and you can have a smoking gun. (after if it is on the internet, it HAS to be true, RIGHT?)
I can also see the ECU compensating for such mods as well, negating the changes you just made over time. It is all a bit of voodoo magic with modern cars.
This is what it looks like without the stock scoop grill.
I'm still working on the mesh project I started 2 weeks ago.
Haven't had much time to get back to it ...

Someone was asking about any performance feel after the install.
Now that I have had it for a couple of week, I can say from my experience it does give it a better feel for performance. I notice on the highway is where the difference is mainly felt for me.
I install the exhaust in 2 weeks, I'm actually installing a Milltek non-res so I hope to make some youtube videos with before and after clips to help others evaluate the difference.
I'm still working on the mesh project I started 2 weeks ago.
Haven't had much time to get back to it ...

Someone was asking about any performance feel after the install.
Now that I have had it for a couple of week, I can say from my experience it does give it a better feel for performance. I notice on the highway is where the difference is mainly felt for me.
I install the exhaust in 2 weeks, I'm actually installing a Milltek non-res so I hope to make some youtube videos with before and after clips to help others evaluate the difference.
Seems to me though, that a more free flowing air filter would show a higher volume of air at lower speeds or a lower throttle position than what the computer is used to seeing.
I'm not sure what changes it would make to compensate. Curious.
I'm not sure what changes it would make to compensate. Curious.
In the good old days, you add a cold air scoop and you needed to reject the carburetor to gain full advantage of the increased air flow.
Now a days the MAF would sense any changes and make adjustments. Very similar to driving in thin mountain air. The system detects the oxygen difference and adjusts to the optimum mixture.
Now the ECU may take the extra air and produce extra power (hopefully) OR dial back and try to maintain the stock parameters and HP as much as possible.
Lets hope for the former rather than the later.






