Mini-review: "Green tag" non-M Z3 rack on E46 M3

[ridebikes]

Howdy everyone, I hope this might help anyone who (like me recently) is on the fence about making this upgrade. tl;dr: Do it!

I recently installed a "green tag" Z3 rack (out of a 1.9L) into my E46 M3. The good news is that all the M3 tie rods hook right up, all you need is the rack itself. I sourced the rack on ebay and had it installed by Edge Motorworks in Fremont, CA (shout out Derek & co!

The reason I selected the rack is based mostly on recommendations read on other forums. While "yellow tag" and "purple tag" both sounded like improvements, the Z3 "green tag" was unique in that it was quick & linear (EDIT: Turns out all those racks are linear, but Z3 is quickest). It seemed like fellow owners who had performance oriented builds spoke the most highly about this feature, since it nullifies that "dead spot" feeling as you begin to turn the wheel.





Here are my impressions after ~100 miles of highway and twisty driving:

• Overall feel is massively improved and notably heavier in a very satisfying way. The first time I was able to set up the car for a sweeping onramp, I literally LOL'd.
• There is a crispness and "electricity" to the steering that was lacking before. I should note that half the inspiration for the swap was a leaking PS system, so some of this may just be maintenance. But overall, I feel like I have a new sense of what the front tires are doing through the wheel.
• I wouldn't describe the steering as nervous or twitchy but it's not relaxed either. I was anxious that highway driving would be negatively affected since the stock M3 progressive steering is designed to be reassuring at high speed. The car does feel less "stable" at speed, but it's nothing that comes close to ruining the car or something. Just means you have to pay attention when you drive!
• Slow speed/parking lot maneuvers take slightly more effort, but nothing unreasonable. Haven't noticed a particularly worse turning radius either.
• Having driven several Porsches w/hydro racks (986, 987, 996), I'd say my car now has parity with that level of feel & detail through the wheel.

Having lurked on this board (and the old one) for a few years, I've often heard the 4.1 gears described as "how it should have come from the factory". I'd say the very same thing about this mod! It so fundamentally changes the way the car behaves and makes every mile more enjoyable.

[repoman89]

While "yellow tag" and "purple tag" both sounded like improvements, the Z3 "green tag" was unique in that it was linear.

Thanks for the review, but wanted to point out that all the common racks are linear: https://nam3forum.com/forums/forum/m...rmation-thread

[ridebikes]

Thanks for the review, but wanted to point out that all the common racks are linear: https://nam3forum.com/forums/forum/m...rmation-thread

I stand corrected! I made different notes from another forum but this appears to be more up to date (and way better researched information). Thank you.

[terra]

Your first picture is an M3 rack. Does look like that last picture is a a Z3 rack with its half stamped steel body.

[akshon]

I too have this rack. Super quick almost too much but I like it. Agree that the 4.10 gears and this rack make the car super lively but still feels oem.

[Lukem3]

Subd

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[specializedbndt]

I actually just did this very swap. Its amazing. The response, feel and turn-in transformed the car. The steering is perfectly weighted as well. Honestly, if feels better than my ZCP rack. Im going to snatch another one and just store it in my attic while they're still prolific.

[Onefastsicilian]

Thanks for your review... What year Z3 did this come out of?

[SpaceJockey]

Also, would you mind sharing the part number of the Z3 rack? The 455 rack in the picture is M3, no? Is the 1.9L Z3 part #32131095575?

[ridebikes]

I actually just did this very swap. Its amazing. The response, feel and turn-in transformed the car. The steering is perfectly weighted as well. Honestly, if feels better than my ZCP rack. Im going to snatch another one and just store it in my attic while they're still prolific.

Couldn't agree more! Glad to hear I'm not crazy in thinking this transforms the car

Thanks for your review... What year Z3 did this come out of?

1999

Also, would you mind sharing the part number of the Z3 rack? The 455 rack in the picture is M3, no? Is the 1.9L Z3 part #32131095575?

👍

[EthanolTurbo]

I too did this swap earlier this year (got a Z3 rack for $35 from a junkyard). Definitely one of the must-do mods for any E46 M3.

[Obioban]

Have you measured it? According to another member on here that did, it's the same rate as the ZCP/ZHP/etc.

Good to see this thread back. I was the one who measured the Z4MC racks on the old thread, I measured a reman one direct from BMW and one that came factory from a car. Both were 50mm\rev linear. I also measured a variety of z3 racks, 1.9 and 2.5s. Again all 50mm\rev linear. I think it's safe to say that until proof of the contrary 1.9l z3s don't have a quicker ratio (read a couple times that some are actually slower, but I've never seen one myself).

Interestingly I also measured a rack that supposedly came from a prototype Z4MC in germany, but it had a Z4M roadster original part#. It also measured 50mm\rev linear.

Sorry can't remember all the part#s off the top of my head. I'll try to update later with them.

That said, it's worth pointing out for people reading this that you can't code the DSC to be happy with faster racks than the ZCP/ZHP/etc-- so a faster rack would result in more DSC intervention, if it is faster. If the Z3 1.9 rack is 50mm/rev, you should code your DSC for the faster rack.

[SpaceJockey]

I have the older MK20, so I always assumed I would basically be limited to driving without DSC if I ever go to a shorter rack.

[lapoune]

Would be very interested in your measurements! I measured a couple of them myself and ratio-wise, they were all the same (at 50mm), mine were all gold bodied though 1.9l and 2.5l. I also tested them in an actual Z3 and steering l2l came out at 2.7t, which was consistent with specs\reports, another reason I believe there isn't a faster rack available.

[old///MFanatic]

1999

Interesting, I’d swear tag shows ‘04?