Z3M Coupe Semi-Restoration ! Progress with PICS !
Aug 26, 2011 | 08:48 PM
#111
Teamspeed Pro
Joined: Nov 2008
Posts: 7,658
From: LA
Dude. Get a diff. BMW intentionally put stupidly tall diff ratios to de-tune the MZ3 and M coupe so that they wouldn't be faster than the M3 (yes, they still are).
Put a 3.73 LSD in. It completely wakes up the car, you put down 18% more torque to the wheels and the gears are more aligned with the power band. Your RPM's are barely 500 higher on the highway, and your top speed is still over 155mph/255kph.
Best part of it is, ANY mid-case e30 diff fits! Just find a 325iS e30 in the scrapyard, swap the flanges and bam, its in! Even the vented diff cover will fit on the new one!
Put a 3.73 LSD in. It completely wakes up the car, you put down 18% more torque to the wheels and the gears are more aligned with the power band. Your RPM's are barely 500 higher on the highway, and your top speed is still over 155mph/255kph.
Best part of it is, ANY mid-case e30 diff fits! Just find a 325iS e30 in the scrapyard, swap the flanges and bam, its in! Even the vented diff cover will fit on the new one!
I replaced the standard 4.1 final gear in my first S2000 with a 4.56.
Great thread!!!
Aug 26, 2011 | 09:31 PM
#112
Teamspeed Senior Member
Joined: Mar 2008
Posts: 512
From: toronto
^^its not misleading, its a mathematical fact
Its cool that you swapped the gear, not too many people do that (at least not in the euro tuning world). Did you find 5th and 6th to be really similar in ratio?
It doesn't give the car any additional power, it just delivers that power to the wheels differently (faster, or at a higher curve, in this case being 18%).
MZ3's should've come with 3.64's or at least 3.46's, 3.15 is just stupid, the car is geared for like 320km/h (which it wont get to without mods, even at 3K lbs)
P.S. i'm moving to calgary in a week, which means valve adjustment + i'll find a 3.73 forsure. I'll report back!
Its cool that you swapped the gear, not too many people do that (at least not in the euro tuning world). Did you find 5th and 6th to be really similar in ratio?It doesn't give the car any additional power, it just delivers that power to the wheels differently (faster, or at a higher curve, in this case being 18%).
MZ3's should've come with 3.64's or at least 3.46's, 3.15 is just stupid, the car is geared for like 320km/h (which it wont get to without mods, even at 3K lbs)
P.S. i'm moving to calgary in a week, which means valve adjustment + i'll find a 3.73 forsure. I'll report back!
Last edited by propr`one; Aug 26, 2011 at 09:33 PM.
Aug 27, 2011 | 12:48 AM
#114
New OG
Joined: Oct 2010
Posts: 1,927
I went through this whole thread earlier this evening and let's just say it was a good reminder of why I love cars so much. You haven't spared the slightest detail in this project and it really gives me the motivation to do the same thing one day with a car. Enjoy it now.
Aug 27, 2011 | 11:11 AM
#115
Teamspeed Pro
Joined: Nov 2008
Posts: 7,658
From: LA
In the case of the Z3M it might make sense, coupled with the fact that it has a 5 speed (even in S54 form).
It is a popular mod on the S2000s as well, I just think it's less "clear cut gain" than most think, and find it more of a compromise. Above all else, it depends how you drive. Track car, great mod. Freeway DD, terrible mod.
In the S2000, I did not find 5 and 6 too similar. 5th become closer to the original 4th, 6th to the original 5th, etc ..
cheers
It is a popular mod on the S2000s as well, I just think it's less "clear cut gain" than most think, and find it more of a compromise. Above all else, it depends how you drive. Track car, great mod. Freeway DD, terrible mod.
In the S2000, I did not find 5 and 6 too similar. 5th become closer to the original 4th, 6th to the original 5th, etc ..
cheers
Last edited by wyatth; Aug 27, 2011 at 11:12 AM.
Sep 7, 2011 | 01:44 PM
#117
Teamspeed Pro
Joined: Nov 2008
Posts: 7,658
From: LA
depends - what is your top speed now?
if it's gear-limited (which i doubt), then it will 18% lower than that. if it's electronically-limited, then it might not change at all - you'll just reach that limiter at a higher RPM.
each gear will accelerate faster (wheel speed and engine speed), but each gear will redline at a lower mph than before, so it is slightly deceiving (you're getting 'there' quicker but not going as far).
if it's gear-limited (which i doubt), then it will 18% lower than that. if it's electronically-limited, then it might not change at all - you'll just reach that limiter at a higher RPM.
each gear will accelerate faster (wheel speed and engine speed), but each gear will redline at a lower mph than before, so it is slightly deceiving (you're getting 'there' quicker but not going as far).
Last edited by wyatth; Sep 7, 2011 at 01:46 PM.
Sep 20, 2011 | 09:29 AM
#119
Teamspeed Senior Member
Joined: Mar 2008
Posts: 512
From: toronto
None. at 7600 RPM with stock sized tires the car will still go 160mph.
i swapped my 2.91 in my 3.38, made a huge difference in that car.
I may actually have the swap done this season, i'll update this thread. If you think 3.73 is too tall, any e30-sized diff will fit (you can find a small case 3.46 out of a euro 633csi that will fit too).
i swapped my 2.91 in my 3.38, made a huge difference in that car.
I may actually have the swap done this season, i'll update this thread. If you think 3.73 is too tall, any e30-sized diff will fit (you can find a small case 3.46 out of a euro 633csi that will fit too).
Last edited by propr`one; Sep 20, 2011 at 09:34 AM.
Oct 10, 2011 | 06:02 PM
#120
Thread Starter
| Teamspeed Senior Member
Joined: Aug 2007
Posts: 898
From: Istanbul / Turkey
None. at 7600 RPM with stock sized tires the car will still go 160mph.
i swapped my 2.91 in my 3.38, made a huge difference in that car.
I may actually have the swap done this season, i'll update this thread. If you think 3.73 is too tall, any e30-sized diff will fit (you can find a small case 3.46 out of a euro 633csi that will fit too).
i swapped my 2.91 in my 3.38, made a huge difference in that car.
I may actually have the swap done this season, i'll update this thread. If you think 3.73 is too tall, any e30-sized diff will fit (you can find a small case 3.46 out of a euro 633csi that will fit too).
