SOLD 2009 E89 Z4 35i DCT only 40k miles No mods. £12,500
- Thread starter Robster
- Start date
Sold
Scottish Borders
Technically a K+N filter in an E89 upto at least 450 bhp a complete waste of time, totally crap filtration..so apart from that great..great way to ruin an engine over time..
Picture wise I'd suggest probably 10+ on the interior in various ways another 1o around the car..all IMHO
Respectfully, I don't agree - as long as filter cleaned and re-oiled regularly filtration is as good as paper filter. They allow better airflow and whilst it doesn't really add any bhp it does improve induction and exhaust sound. Never had any issues in over 10 years - people can have issues with them if they over oil them. As it says in the ad - still have paper filter so new owner can swap back if they want. Thanks for your opinion and advice though....
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It’s your call ..for any body considering buying a car with a k+n filter fitted for any period of time it will have ingested far more dirt than it would have had it used the factory filters..
Having extensively dyno’d all sorts of filters on both my 20i that went from 185 to 305bhp and my 35is that went from 335 to 550bhp inc DCIs Foam K+N panel filters open airbox no airbox no lid I can state that within experimental error there’s zero or little improvement in performance..
For those interested in how bad k+n filtration is this chart refers…
Thanks for trying to sabotage my sale....I could have created those charts with a pencil and crayon - no data source quoted. Unless you're driving in the Sahara a well maintained K&N filter is more than up to the job. This was a classified ad - your criticism should be kept in the discussion forums if you're so keen to put your point across and not used to try and undermine my sale. You have no evidence whatsoever that my car has been affected by the use of a K&N filter. The filter has been cleaned and re-oiled annually and only does between 200-400 miles a year. It has been regularly maintained by Munich Legends and BMW main dealer. No need to respond - you've made your (incorrect) point and no doubt will have put people off buying my car - thanks I thought this was a friendly helpful forum rather than used to undermine other members.
Don’t worry. It shouldn’t put off potential buyers. It looks a smart car at a good price with some of the usual jobs having already been done. More pics though would be good. On the k&n front I also suggest standard is always better so just take it out and take off the stickers. If nothing else it takes away any semblance of boy racer. And your car is a smart non-boy racer spec don’t ties in with that
Completely get your frustration. As others have said maybe worth getting some more pics. You’re car itself is in one of the more desirable colour combos for an E89, low mileage and you have had some of the big jobs done that makes it appealing. I don’t think you will struggle to sell this. GLWS
ISO 5001 tests
project200.com.au/dm-iso5011/
Well known now, belatedly once they did proper testing as to how bad cotton gauze filters are for filtration and with modern airboxes zippo improvements over stock filtration.
The dust in the Sahara is the least of your problems.. ..small diameter dust particles that pass easily through a cotton gauze filter do damage over the long term..just like cigarettes..a few puffs not an issue, smoking a long time..hello cancer...so yes sure the differences over a few hundred miles is negligible, over ten of thousands it isn't.
If you'd just said I did it cause I like the noise then who cares..you were the one making assertions without any evidence.
Spouting crap isn't going to get you anywhere here..
Thanks both for your more positive contribution. Colour combo is the best imho. I hope people aren't put off as it really is in great condition and drives beautifully. Any potential buyer is free to swap out the filter as I kept the paper one. It does such low mileage (only 200-400 per annum). Hopefully Mr B21 has made his point and will leave it there now.....will upload more pics as suggested. Sadly as I type this Mr B21 has become offensive suggesting I'm talking crap
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At the summit of the picturesque fens
I think you will get more interest from the auto trader advert than on here. It maybe worth mentioning on the auto trader ad about the injectors and fuel pump as these are known weak point and a real plus that they have been done
Just ignore him.....most do!
Your car looks a good prospect for someone and anybody with half a brain is not going to walk away because of a perfectly good K&N filter. They have sold millions of them, you know!
Just ask one of the mods to remove the posts which aren't relevant to the sale ad. I have sold several cars on this forum, all to very nice people (including two E89s). It is a good place to advertise, as the quality of potential buyers is very high.
To the right person the HPFP change and injector replacement will be worth a lot, might be worth adding the dates these were done. If I was looking, that would change a £12k 2009 N54 from "wouldn't touch with bargepole" to genuinely interested.
Don't want to wade into the debate about whether K&N filters are any good (because I don't know and frankly don't care), but I've found that any modifications definitely do put potential buyers off, so it would be worth switching the filter back to original for an easier sale.
Don't want to wade into the debate about whether K&N filters are any good (because I don't know and frankly don't care), but I've found that any modifications definitely do put potential buyers off, so it would be worth switching the filter back to original for an easier sale.