Does anyone know the stiffness of the Z4M Coupe chassis? Also how does it compare with the E90/92?? Thanks

32,000Nm in the Z4 M Coupe chassis. 24,000Nm is the E90 sans fold down seats, ~19,500Nm is the E92.

If I recall.

Bingo on the seats... Not bad as sedans go. I used to gripe because the fold down area was so narrow as that area is still built up, but while it is a sacrifice, there's a reason.

The z coupe's really are a sweet chas.

I didn't realize ho much I liked this car till I got a little out of sorts in it and corrected so easily. The composure of this car under stress is just insane.

32,000Nm in the Z4 M Coupe chassis. 24,000Nm is the E90 sans fold down seats, ~19,500Nm is the E92.

If I recall.

Thanks.. I heard the E92 is stiffer than the E90? Man i really need to get a Z4M! Is there somewhere i can find this info on the internet? Thanks

Thanks.. I heard the E92 is stiffer than the E90? Man i really need to get a Z4M! Is there somewhere i can find this info on the internet? Thanks

Coupe counterparts are never as stiff as the sedan chassis they're based off of. The E46 sedan was significantly stiffer than the coupe. 14,000Nm vs. 12,00Nm. E36, same thing. What you may have read, is that the E92 chassis is stiffer than the E46 sedan or 50% or so stiffer than the E46 coupe chassis.

By the way, here's a short discussion with some decent info on some BMW models:

http://forum.rscnet.org/archive/index.php?t-210895.html

Torsional rigidity info on the MZ4 Coupe:

http://www.tuninglinx.com/html/2007-bmw-z4-30si-m-coupe-01.html

- Precise and agile handling thanks to a body torsional rigidity of 32,000Nm/degree.

http://www.pistonheads.com/doc.asp?c=100&i=15562

Scoring 14,500Nm/degree in BMW’s torsional stiffness test, the M Roadster is pretty stiff for an open car, and despite its wide 225/45 and 255/40 rubber on 8.0J and 9.0J x 18-inch alloys rubber, scuttle shake on poor roads in minimal. Even so, it does not come close to the Coupé’s impressive 32,000 Nm/degree, which is more than double the Roadster’s rigidity.

Here's another good database of torsional rigidity:

http://forums.nasioc.com/forums/showthread.php?t=1266524

BMW E90 : 22,500 nm/deg (I was off by 1,500Nm)
BMW Z4: 14,500 Nm/deg
BMW Z4 M Coupe : 32,000 Nm/deg (BMW AG's press)

I have not been able to find any solid torsional rigidity data on the E92, but some info suggest that it's 50% stiffer than the E46 chassis, which would leave it square in the 18,000Nm-20,000Nm range.

All info above supplied via Google Searches.

Thank you Hack. Very informative information. I just can't believe the Z4M... This makes me want the car that much more.

By the way, here's a short discussion with some decent info on some BMW models:

http://forum.rscnet.org/archive/index.php?t-210895.html

Torsional rigidity info on the MZ4 Coupe:

http://www.tuninglinx.com/html/2007-bmw-z4-30si-m-coupe-01.html



http://www.pistonheads.com/doc.asp?c=100&i=15562



Here's another good database of torsional rigidity:

http://forums.nasioc.com/forums/showthread.php?t=1266524



I have not been able to find any solid torsional rigidity data on the E92, but some info suggest that it's 50% stiffer than the E46 chassis, which would leave it square in the 18,000Nm-20,000Nm range.

All info above supplied via Google Searches.

Coming from an Elise that is known as a very stiff chassis I must say the Z4 M feels just as rigid.

yeah definitely feels solid.