E46 M3 vs E86 Z4M as a track car

[shibui]

I wasn’t very fond of the E86’s design when I was younger, but now think it has aged quite gracefully. Has anyone driven both on track? As one of two other M cars to officially receive the S54 I’d love to give the E86 a go but they aren’t the most common things around.


If you update the M3 with the Z4M steering rack and stiffin up the chassis, does it still feel less tight than the E86 and its natural rigidity?

I’m also surprised that out of the factory the weights are supposedly pretty even.

[LeeForst]

My brother has a 2007 Z4M and I have an E46 M3 and both with TCK suspension, stock motors, we are staying with each other at Lighting and Thunderbolt here at NJMP in the intermediate run group. The advantage of the 46 is that I have way more trunk space I'm always the guy hauling the coolers, etc.

Regardless, the Z4M is amazing and as Obioban rightly noted, " they are in their natural habitat on the track"

[Obioban]

From a track perspective, being able to put 4 tires in the back seat and still have a pretty large trunk for all your tools/tent/chair/etc is a huge perk. Stock vs stock, they're not that far off each other, and the e46 enjoys hugely better aftermarket support (beneficial for tracking). More/better suspension options, more/better power options (mostly because the Z4M uses a different ECU that isn't nearly as open sourced as the MSS54), multiple wheels designed specifically for tracking the e46 M3, etc.

I wouldn't put the Z4M rack on the e46M. You can't program the DSC to be happy with it, and a fast twitchy rack isn't beneficial on track where you want to be smoooooth in your inputs. Plus, you're not going to find any corners on track where you're crossing your arms with the stock M3 rack, much less something like the ZCP/ZHP rack.

[lapoune]

z4m rack ratio is the same as zcp, check out the comprehensive steering thread for more info. Wish it was stickied honestly people have been confused\misinformed about this for decades at this point..

[Slideways]

z4m rack ratio is the same as zcp, check out the comprehensive steering thread for more info. Wish it was stickied honestly people have been confused\misinformed about this for decades at this point..

I recall that is the roadster, not the coupe.

[lapoune]

I recall that is the roadster, not the coupe.

Check out this thread: https://nam3forum.com/forums/forum/m...rmation-thread

coupe is same ratio as zcp, roadster is slower. Until proof of the contrary zcp is easiest swap\best rack for e46 (that includes z3 1.6 which is same ratio). Measured a bunch of these myself, and others have confirmed. Unless some weird fuckery by bmw the unconfirmed #s are likely wrong.

[ZiMMie]

Z4 chassis is stiffer than e46.

The Z4 makes a better track car than the e46.

[Obioban]

Check out this thread: https://nam3forum.com/forums/forum/m...rmation-thread

coupe is same ratio as zcp, roadster is slower. Until proof of the contrary zcp is easiest swap\best rack for e46 (that includes z3 1.6 which is same ratio). Measured a bunch of these myself, and others have confirmed. Unless some weird fuckery by bmw the unconfirmed #s are likely wrong.

ZHP is the same ratio as ZCP and supposedly (the rack doctor explained why) better feel... which would make it "best" imo. I say "best" because I prefer the stock M3 ratio to the ZCP/ZHP/whatever else ratio.

[Obioban]

Z4 chassis is stiffer than e46.

The Z4 makes a better track car than the e46.

Stock vs stock, once you're at the track with all your stuff, this is true.

... but nobody is stock and you have to get your stuff to the track.

[Icecream]

Stock vs stock, once you're at the track with all your stuff, this is true.

... but nobody is stock and you have to get your stuff to the track.

Roof rack??

[lapoune]

ZHP is the same ratio as ZCP and supposedly (the rack doctor explained why) better feel... which would make it "best" imo. I say "best" because I prefer the stock M3 ratio to the ZCP/ZHP/whatever else ratio.

yes I meant only ratio wise (which he seemed to be looking for), zhp too of course.

[Speed Monkey]

Nordschliefe Lap Times per https://www.supercars.net/forum/thre...p-times.41550/

7:50 - CSL
8:15 - Z4M Roadster
8:22 - M3 E46 Standard Model

When it comes to a non-modified M car attainable here in the US, it appears the ZM wins. With mods and sticky tires, who knows...🙄

[ZiMMie]

Stock vs stock, once you're at the track with all your stuff, this is true.

... but nobody is stock and you have to get your stuff to the track.

Not to mention weight as well. It doesn't take much to make the z4 light compared to the e46.

No Matter what mods you put on the e46 it will come short on chassis side. Unless you put in cage. A cage will also bump up the weight significantly since you will need more Material in the e46.

Im a huge fan of the e46. If I were to build a track car and had an option to choose I wouldn't even think twice on choosing the e86.

Maybe op will have a trailer for the car.

[Obioban]

Nordschliefe Lap Times per https://www.supercars.net/forum/thre...p-times.41550/

7:50 - CSL
8:15 - Z4M Roadster
8:22 - M3 E46 Standard Model

When it comes to a non-modified M car attainable here in the US, it appears the ZM wins. With mods and sticky tires, who knows...🙄

I would be pretty confident in saying that if all the cars were on the same tires, the lap time differences would be ~half what we see there. The M3's PS1s or CSC1s were already long outdated by 2001 (stock on the e36, as well), the CSLs PSCs were well ahead of their time, and the Z4Ms stock tires were right about on par for the era. Put all 3 cars on the same tires and they'll get a lot closer together.

[Obioban]

Not to mention weight as well. It doesn't take much to make the z4 light compared to the e46.

No Matter what mods you put on the e46 it will come short on chassis side. Unless you put in cage. A cage will also bump up the weight significantly since you will need more Material in the e46.

Im a huge fan of the e46. If I were to build a track car and had an option to choose I wouldn't even think twice on choosing the e86.

Maybe op will have a trailer for the car.

If you're trailering, and live in a world where those are the only two cars that exist, sure.

I had a dedicated track car and never will again. Trailering was misery, and almost ruined tracking for me. Back in the e46, the drive to/from the track is part of the event.
Side note: M3 has more weight to lose and a cage doesn't add that much-- my dedicated track car was an S50B32 e36 M3 with full tied into shock tower, chassis stiffening cage, and it was 2315 lbs with a half tank of gas.

All that said, if you're buying a sports car that compromises all semblance of practicality, I wouldn't get one based on a sedan chassis (Z4M). Better to get something built from the ground up to be a sports car-- Boxster/cayman, corvette, 911, miata, whatever. As you would put it, the modified sedan chassis will always come up short compared to something designed from the ground up to be a sports car. Once you've given up on the practical benefits of the sedan platform, there's other options out there that probably make more sense (that, perhaps ironically, are often more practical as well-- corvette trunk is huuuuuge).