question about bmc air filter's.... - The Unofficial BMW M5 Messageboard (m5board.com)

LI-M5 · 2nd July 2007, 19:50

hey guys so a couple of weeks ago i was home sick messing around on the board and i ran into the "bmc air filter's work much better" thread and of course being a sucker for modds i ordered a set, i got them last week and threw them in and i defenetly felt an improvement esp towards the tops of each gear..defenetly the chirp into 3rd gear got even more violent defently noticeable..

but now as i drive around a little more and get more seat time im feeling like i've lost a lot of low end beans, it feels like the car did before i got the 3.91 diff where its like dead from 1k-4200k rpms then its an animal..now this is ok but the 3.91 diff really improved this.. it woke up the entire bottom half of the rpm range and thats what i love about it.. but the last couple of drives have left me feeling like its not there anymore..

so my question to those that have this modd and to those who would be able to answer, is it poss that the bmc dropp in filters that i dropped in actually took away some (alot) of my bottom beans ???

has anyone else who did this modd felt anything similar ???

or is it that im just smokin crack and have no idea what the hell im talking about

thanks neil...

Wayward · 2nd July 2007, 21:37

Neil, I don't have the BMCs yet, and we know it takes the ECU some time to adapt, but have you considered reinstalling the oem filters to compare the difference?

LI-M5 · 2nd July 2007, 22:15

Quote:

Originally Posted by Wayward

Neil, have you considered reinstalling the oem filters to compare the difference?

gonna do it as soon as i get hm today,, will report back asap....

Wayward · 3rd July 2007, 05:35

Thanks Neil, really curious as to your findings.

hbpetrides · 3rd July 2007, 21:26

I have got them in now for about 2 months, I am not sure if the performance is gone, but for sure once we get used to the power, it doesn't seem to impress any more.
The only way that I was measurering the improvement apart from feel, is by the amount of wheel spin I get on a certain road that I use every day, in second gear when I floor the throttle, and that seems to be the same as always.
Did you make any other mod?
The only mistake is that one of us who installed the filters should have done a before and after Dyno.
That would clear things out for sure.

LI-M5 · 7th July 2007, 00:02

sorry it toook so long but i did revert back to stock and i must say i did notice a difference !! i think that the bmc air filters help out alot in the top of the gears but defenetly affect the bottom..gonna keep testing and will post back

///Marshall · 7th July 2007, 01:58

Hrm...just got mine today. Not the news I wanted to hear.

hbpetrides · 8th July 2007, 13:28

I will also try to go back to stock and try for a couple of days just to see.
The only thing that I can tell for sure is that if I do not drive the car on a highway for about a week, it feels a little jerky, but once it runs for 10 miles or so on a highway, it becomes transformed.
I will let you know if I feel anything different with stock.

cpiguy · 8th July 2007, 21:31

This is amazing. I just got mine on Friday. After this, I'm a little reluctant to install them. I always thought better breathing meant better performance. At least that's always been my experience.

I'd love to here from others that have installed the BMC's and or any other after market performance filters.

Is there a way to pull this post over to the M5 site?

Wayward · 8th July 2007, 22:07

Quote:

Originally Posted by cpiguy

Is there a way to pull this post over to the M5 site?

There's a current thread on the BMCs on the E60 M5 forum here.

As an FYI, you can always post a new thread on that forum and provide a link to a thread on this form (asking that they reply in the linked thread) so that most replies can be contained in a single thread. This is the ideal way to prevent the creation of duplicate threads on identical topics.