Afe CAI Install DIY and Thoughts

[White05X3]

Here is a link to a complete write-up on installing the Afe CAI

http://randall-harris.com/afe_install.html

Here are my thoughts:

1. The installation was unbelievably easy. But for my mistakes and taking pictures for the DIY it would have taken less than 30 minutes.

2. The sound is INCREDIBLE. There is a tiny amount of intake whistle at low RPM's and small throttle openings but it is not obtrusive. At WOT the car sounds so much better!!!

3. My initial impression is that there is no power difference. However I will give the ECU time to adapt to the higher airflow and reach a final conclusion in a few days. It did seem like the car was quicker towards the end of my test drive, but that could be a placebo.

4. The quality of the Afe kit is very impressive. Everything fit reasonably well.

Enjoy the video at the end of the install DIY. I truly and deeply apologize for the poor quality of the video, but my intent was to capture the sound not the images.

[asawadude]

Thanks for the great writeup, Randy! You should bundle up the writeup and submit it for inclusion in the DIY section.

[r6girl]

sweet sound! nice write-up too, randy! this should definitely go in the diy section here. now i'm tempted to try this myself...

[Rick in Prescott]

Increasing air flow sounds great. What CFM does a stock system flow and how much more will the new CAI flow? With more air going in, if that is in fact, a fact, do you need to update your exhaust to accomondate all the extra airflow or will the stock setup work fine? Last question? Do you think it cost more to build a CAI, (at high production quantities) than it does the stock pieces we have? Why wouldn't BMW try to extract more HP with such a simple mod and include them as stock pieces? Sorry for all the questions but I've never done much more than a K&N air filter, (a waste of money) to any of the 15 BMW's I've ever owned and wonder what I might be missing.

[White05X3]

Maryanne - Thanks! It is a really easy DIY! Check back in a few days as to whether or not I think it is worth it. The manufacturer advertises 20hp but there is NO way I expect to get that. 5-10 would be the max if I am really lucky. Assuming that, is $625 a good deal? I got mine on ebay for far less or I would not have done it.

Rick - There are many good reasons why manufacturers do not do certain high performance things. For example, with this CAI there is a distinct whistle that I suspect most customers would find unacceptable. Also some CAI designs would probably be more likely to ingest water in bad weather. This one seems reasonably safe to me and no more vulnerable than the stock box. Also this is made of powder coated aluminum which I suspect is more expensive than the plastic that comes from the factory. I have no idea how much more air this setup flows but will look into it. I doubt it is enough to mandate any other mods though.

As to the question about the exhaust, that would probably help a bit but most of the flow is stopped by the catalytic converters. The main advantages to be gained from an exhaust are lighter weight and different sound quality. Supersprint makes a nice system for the X3 that will replace the entire system from the exhaust manifold back if you choose. Or you can just get a cat-back muffler.

Happy Thanksgiving everybody!!

[Rick in Prescott]

Ingesting water and aluminum are easy things to overcome. In production, blow molding would most likely be the answer and stopping them from ingesting water seems like a design issue that BMW could easily overcome. There's a fine balance of $$ vs HP and I'm thinking BMW most likely has better things to spend money on. Thanks for your comments.

[MysticBlueX3]

Nice write up I've been meaning to get an AFE intake for quite some time now. But been held back because of their "pending" C.A.R.B. certification and spending all my money on my new bike and gear. Did they every get C.A.R.B. certified? If you don't mind asking where did you get it from and how much? Intake sounds great

[White05X3]

Originally Posted by MysticBlueX3

Nice write up I've been meaning to get an AFE intake for quite some time now. But been held back because of their "pending" C.A.R.B. certification and spending all my money on my new bike and gear. Did they every get C.A.R.B. certified? If you don't mind asking where did you get it from and how much? Intake sounds great

I have not heard that they have a CARB certification. Frankly the install was so easy that if I need a smog check I will just put the OEM back in.

I got mine from ebay and paid $200. Unfortunately it was a private seller and not some store.

If you elect to get one and want help installing it, let me know.

[White05X3]

One week later here are my thoughts on the Afe:

1. The sound is amazing at WOT. The whistle at low throttle and low RPM's is getting a bit annoying but I can live with it.

2. The car feels more responsive but not necessarily faster. There are however certain factors that could be contributing to that feeling:
A. I have been playing around with the power so the adaptive throttle has probably adjusted to my more aggressive driving style
B. It is cooler here than it was when I installed it
C. The ECU has probably adjusted a bit to the increased air flow
D. The sound makes one belive there MUST be more power
E. I really want it to be making more power to justify my $$$

There have been no CEL's or running problems to date (knock on wood).

While I don't feel so bad spending $200 on it, I would not spend their retail price on one of these. If you can find a cheap one then it might be worth it. If not, I would recommend against it. There is just not enough HP for the cost IMHO.

[Juanted]

Very nice write-up, and cool video, too! Thanks a bunch for sharing your experience and DIY.

Juan