E46 M3 DMS Upgrade

[cammy]

Hi All

This is my first posting on the BMW forum, so forgive me if this question has been asked previously.

Has anyone out there done the DMS upgrade on their E46 M3. I know it would invalidate my warranty (if detected) but I am seriously considering it, but have the follwong concerns:-
1) Do the brakes handle the extra power alright
2) Will the upgrade affect the longetivity of the engine and components i.e. through extra stress
3) Affect on insurance premiums ?

At £750, it seems a pretty good bargain.

Any response would be greatly appreciated.

[john_p]

Personally, I would advise against it. If anything were to happen to your engine then BMW would probably check the DME to ensure no 'aftermarket' software had been downloaded. I think to do this they need to send it back to Germany.

With a new engine costing >£10k do you really want to take the risk?

I'd also question the real BHP gains achievable, the M3 engine is in such a high state of tune .. if you can get 360bhp from software only why did BMW use different cams, intake and software on the CSL to get the same amount of power?

[cammy]

Thanks for the repsonse john p.

I know what you mean by the risk. My gut feeling is no, but it has been mentioned in the club magazine and apparently it is undetectable because the diagnostic only checks the core data/software is alright.

But as you say, at £10k an engine!?

[hughjayteens]

Does sound rather risky to me. Most ecu remaps will just give an improved response rather than big power gains.

>> Edited by hughjayteens on Monday 16th August 23:30

[Geoff_33]

Go to BM3W.co.uk

There been a discussion on the DMS conversion this week with actual members who have had the conversion and then went on to the rolling road to get bhp/torque figures. From memory, some of the E46 M3's were getting 370-380bhp.
The improvement with the CSL wasn't as good due to the already high state of tune.
DMS are obviously a good company, just look what they did to the Porshe (EVO mag) on the high speed day testing.
Not sure on the price etc. I'm sure you'll get lots of answers from the guys on the site.

[JohnRS4]

With the recall that is currently out regarding the engine problems on certain E46 M3s I would stay well clear. If you suffer an engine failure and the dealer finds you have altered the ECU programme then your warranty will be out of the window. Not sure that the benefit you will get on this particular engine is worth the risk

[cammy]

Thanks for the replies. It is not something I would contemplate within the warranty period. I understand that my engine is OK, i.e. out of the time bracket which affected the M3 recall.

I will try the other site.

Cheers