2001 Z3 3.0 modification suggestions

[Damaged DNA]

I recently bought a Z3 roadster and I want it as a tuner car essentially. My biggest problem is that it has approximately 50k miles on it, and before modifying any performance defining aspect of it, I think I want to enjoy it's stock engine like the bimmer gods intended. At least until it hits 100k at least.

In the meantime, what performance upgrades could I perform now and what cosmetic upgrades do you all prefer?
My first consideration is halo headlights and possibly new taillights as well. I'm kind of new to this so I want to start small.

[pbonsalb]

It’s an M54 engine so I’d start with researching that and I would it wait 50k miles to mod. Definitely drive it a few months so you can really experience the car and learn what you want to modify. Can’t help with the cosmetics—I am a performance person.

[Damaged DNA]

That's fair. so far my only gripe with the driving experience is that the transition from first to second isn't exemplary. The rpms don't drop fast enough when disengaging the clutch to transition between gears smoothly in a reasonable time. I'm currently trying to fix some small issues with the car as well.
Like for example, I lose rpm while driving with my lights on. I thought a new alternator would fix it, but it did not.

What performance upgrades have you installed?

[MauiM3Mania]

Moved discussion to model specific sub-forum.

[spfd72]

1st year of “drive by wire” therefore likely cause of rev-hang. The m54 3L is one of BMW finest mass produced engines. I am by no means a depth of knowledge but from the factory I am not sure there is a lot of gains on that engine (the ZHP version in the E46 made 235 hp which I believe was all software-derived). I agree that driving as is might be rewarding.

[KBH22102]

It's 21 years old and even though the miles are low, maintenance needs should addressed first - plastic cooling system parts, rubber suspension bushings, fluids, and tires. The M54 is a pretty great engine already; a 3.46 diff will keep it in a sweeter rev range and you will get more immediate acceleration. The car responds well to suspension upgrades - poly subframe bushings and FLCAB's, Koni or Bilstein shocks and lowering springs; maybe coilovers if you plan to track. Good 200 TW tires will also enhance handling.

[Damaged DNA]

This helps a lot and explains some things I'll need to take a look at.

[IndianaRoadster]

This helps a lot and explains some things I'll need to take a look at.

As far as cosmetics go, to each his own. I have done a few, but I always make it so it can be reversed back to stock. You mentioned headlights, I to thought the front needed a little massaging. I decromed the headlights surrounds and deleted the Chrome around the edge of the kidney grills. It gives it a more updated look I feel. I made a functional splitter that ties in with the bottom of my oil cooler. Also made a spoiler that is strictly bolt on can be unbolted and you would never know it was ever on.
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[z3forlife]

Your shifting issue could be related to the clutch master/slave line. The rubber line will bulge slightly and worsen with repeated use like on a longer drive. It’s 20 YO rubber. When you say you loose rpm do you feel a power drop or just indicated rpm drop

[Damaged DNA]

Your shifting issue could be related to the clutch master/slave line. The rubber line will bulge slightly and worsen with repeated use like on a longer drive. It’s 20 YO rubber. When you say you loose rpm do you feel a power drop or just indicated rpm drop

I had recently installed a 120amp alternator thinking that it may be a power issue, replacing the 90 amp one that came with the vehicle. The issue only occurs when my lights are on. The rpm drop I experience is a power drop. My vehicle will lurch slightly and lose rpms even with the accelerator pedal depressed. It will recover after a few seconds, but it will happen maybe once ever 20 seconds while driving.

[z3forlife]

You should go to the diagnostic thread and setup a laptop to pull codes. It’s a deep thread but the software is on the first page. You’ll have to source the cables but it will give you accurate info. There may be shadow codes or active codes that haven’t set a check light yet. With DBW it may be a issue with the throttle valve motor or even the gas pedal or ECU.

[Damaged DNA]

You should go to the diagnostic thread and setup a laptop to pull codes. It’s a deep thread but the software is on the first page. You’ll have to source the cables but it will give you accurate info. There may be shadow codes or active codes that haven’t set a check light yet. With DBW it may be a issue with the throttle valve motor or even the gas pedal or ECU.

Thanks, I'll take a look

[328 Power 04]

There's a certain level of (annoying) programmed revhang in the M54 cars.
Unfortunately, none of the bigger tuner names do anything to address this. They're all going for +4 deg advance, rev limiter rise, speed limit removal, and bam... "tuned".

There is so much more that can be done in the tune for those.

[bdiefAZ]

Does the car have a clutch delete valve? If so, remove it!

Small Mod:
https://www.bimmerforums.com/forum/s...d-for-M54-cars