M3 tuning n stuff

M3 tuning n stuff

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Discussion

mondeoman

Original Poster:

11,430 posts

268 months

Monday 14th June 2004
quotequote all
Had my M3 for just over 3 weeks, and, as usual, I'm looking to, ermmmm, change things a little bit. Me? not satisfied? never

On my list so far are the following:

K&N Filter
De-cat
Steering mods.

Has anyone got any feedback on whether the K&N and de-cat will do anything for the performance? The way I figure it anything that improves the breathing has to be good.

Steering - its just way too light for my liking, so how do I go about reducing the pump pressure to put a bit more weight back into the system?

rich_b

694 posts

248 months

Thursday 17th June 2004
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BMW (especially M3) exhausts arent too restrictive so a decat may not be worth the hassle.

Not sure about the K&N gains, but I'd go the whole way and get a GruppeM

DoctorD

1,542 posts

258 months

Thursday 17th June 2004
quotequote all
Induction changes don't really make much of a difference apart from altering the responsiveness (but no HP or torque gains). So neither a Gruppe M nor a K&N filter will help, although the Gruppe M will sound better (but at quite a cost). You would need to stretch as far as an alpha-N system similar to the CF induction on the CSL or there's one made by Delage Sports in France (for a cool £4000-£6000).

Exhaust will make a difference, but not the back box. You need to consider fitting something like the Supersprint Race Cats which are 100 cell cats compared to the OEM 200 cell items. They will provide around 5-6 extra horses at the rear wheels. You can also replace the centre pipe/silencer with an unsilenced pipe (also available from Supersprint). So you're looking at a maximum of between 5-10bhp from the exhaust.

Some people will suggest modifying the ECU, but the only way to safely extract more power from the M3 engine without drastically compromising reliability is to re-map alongside a change in the oily bits (i.e. cams). Best reputation for achieving results is with Kelleners Motorsport in Germany, but again you're talking £5000-6000 for perhaps an extra 15-20bhp.

If you haven't already done so why not log onto www.bm3w.co.uk where you will find many other M3 owners who've tried out all the available options on the market.


p.s. to improve the feel of the steering I would suggest altering the geometry to increase negative camber and provide a little more castor at the same time, that will provide more feel and feedback whilst improving stability as you turn in to corners. Your BMW dealer will be able to sort that out for you, just ask to have your settings increased towards the outer limit of the factory prescribed tolerance. You could consider fitting the steering rack from a CSL (which has a lower ratio) but that would also be rather expensive and difficult to get hold of. Otherwise another suggestion would be to experiment with different makes of tyre.

>> Edited by DoctorD on Thursday 17th June 23:54

fergus

6,430 posts

277 months

Friday 18th June 2004
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DoctorD said:
You would need to stretch as far as an alpha-N system similar to the CF induction on the CSL or there's one made by Delage Sports in France (for a cool £4000-£6000)


Alpha-N refers to the engine management side of things, with 'alpha' being the throttle angle (from the throttle position sensor) and 'N' being the current revs. Neither of these have anything to do with induction as such. A car running an alpha-N set up would ignore airflow.

... An element of confusion I think?

DoctorD

1,542 posts

258 months

Friday 18th June 2004
quotequote all
I'm aware what an Alpha-N system is, I was using it to illustrate the point that merely funnelling more air through a system designed around an air mass metre will not provide the gains that might be imagined. BMW chose to improve the inflow of air AND the way the engine management system utilised this air in the CSL. Hence improving the front end of the induction system (as in the GruppeM product) will not be as useful as some people think and certainly not good value for money.

fergus

6,430 posts

277 months

Friday 18th June 2004
quotequote all
granted!