Not joined yet? Register for free and enjoy features such as alerts, private messaging and viewing latest posts and topics.

Why does the 35is speedo stop at 160mph?

Specific discussion about the E89 2009 Z4 (sDrive35is, sDrive35i, sDrive30i, sDrive23i)
User avatar
Mr Tidy
Legend
Legend
Posts: 23608
Joined: Wed Jul 02, 2014 12:18 pm
Location: North West Surrey

Why does the 35is speedo stop at 160mph?

Post by Mr Tidy » Wed Jul 19, 2017 11:53 pm

ibroker wrote: Wed Jul 19, 2017 7:12 pmAt 340hp the 35is would never make 180mph. Even unlimited it would struggle to pass 160ish. The jump in horse power required at those speeds to pass 165plus to make 180mph is massive.

Its a great car without question, but kid yourself not. Its not in that league.
I'd be amazed if a 35is struggled to get past 160mph - even E46 330is had a 155mph limiter despite having only 231bhp!

I'd be amazed if my E86 couldn't do over 160mph de-restricted - a de-restricted 35is or M surely ought to get past 170mph, but obviously not on the M6 officer! :roll: (It's far too busy)! :lol:
Coupes because stunning!
Current - Silver Grey MC, Imola Red heated Nappa & carbon trim. Aeros, H & R Coil-overs, 224s, OE Strut brace, Nav, cup-holders, DSP Hi-Fi, pdc, cruise, MFSW, no CDV! E90 330i daily
Gone - Montego Blue
Gone - Ruby Black

User avatar
buzyg
Legend
Legend
Posts: 26423
Joined: Fri May 20, 2011 6:11 pm
Location: Cornwall

Why does the 35is speedo stop at 160mph?

Post by buzyg » Wed Jul 19, 2017 11:57 pm

Does any one have the gear ratios for a 35is? Including the final drive. I can't find them. :(
Image

User avatar
buzyg
Legend
Legend
Posts: 26423
Joined: Fri May 20, 2011 6:11 pm
Location: Cornwall

Why does the 35is speedo stop at 160mph?

Post by buzyg » Thu Jul 20, 2017 12:07 am

sunnydays wrote: Wed Jul 19, 2017 10:55 pm
buzyg wrote: Wed Jul 19, 2017 6:38 pm
sunnydays wrote: Wed Jul 19, 2017 6:32 pm


Torque, weight, gear ratios, tyres, downforce.

Considering the 35is spanks the Z4M from 0-60, 0-100 etc.... its not surpising it has a higher top speed
Could you kindly show me some physics, or some official proven figures please. The physics I was taught say it's unlikely.
My calculations based off
Drag coefficient of 0.34
1.96m sqd area
3500lb kerb weight
340 bhp

Gives a theoretical max of 185mph...

One thing you have not accounted for is the under rating of the N54 engines, it was proven that the N54 turbos put out approx 20-30bhp more than factory figures. BMW has done the same on some other turbo engines ie the M4

There is a 35is delimited with a slight tune comfortably hitting 190mph on youtube measured via GPS. Video below.....

What has kerb weight to do with it? :? Also be sure you are using the power at the wheels and not at the crank. Other wise the figures would suggest a Z4M can do 185mph also and it simply can not. That was my point. The two cars will have very similar unlimited top speeds, as they have similar power, similar cd figures and similar frontal area and the Z4m's is around 171mph.
Image

User avatar
Pastry
Senior Member
Senior Member
Posts: 2288
Joined: Wed May 25, 2016 5:01 pm
Location: South East

Why does the 35is speedo stop at 160mph?

Post by Pastry » Thu Jul 20, 2017 7:13 am

sunnydays wrote: Wed Jul 19, 2017 11:33 pm
Pastry wrote: Wed Jul 19, 2017 11:11 pm
sunnydays wrote: Wed Jul 19, 2017 10:58 pm

Funny how handling always comes up yet the 35is beats the M in almost all track tests :wink:
Heard it all before :roll: I've had both, so I know how they drive :poke:
Im not refuting how the car feels to drive. I am simply refuting people saying it is a poor handling car :). The fact it beats the M around the track speaks volumes
People exaggerate about its poor handling, just like you exaggerate about how it 'spanks an M from 0-60' by 0.2 seconds :roll: As for how quick it can go round a track I couIdn't care less. If I wanted a track car it certainly wouldn't be an E89, unless the track was Santa Pod :poke:
991 Carrera 2S
Now gone:
2008 Z4MR Midnight Blue Metallic
2006 Z4 3.0si sport Ruby Black
2006 Z4 3.0si sport Titanium Silver
2010 Z4 23i Msport and a 3.0i

User avatar
sunnydays
Member
Member
Posts: 983
Joined: Fri Sep 23, 2016 7:50 am

Why does the 35is speedo stop at 160mph?

Post by sunnydays » Thu Jul 20, 2017 8:37 am

Pastry wrote: Thu Jul 20, 2017 7:13 am
sunnydays wrote: Wed Jul 19, 2017 11:33 pm
Pastry wrote: Wed Jul 19, 2017 11:11 pm

Heard it all before :roll: I've had both, so I know how they drive :poke:
Im not refuting how the car feels to drive. I am simply refuting people saying it is a poor handling car :). The fact it beats the M around the track speaks volumes
People exaggerate about its poor handling, just like you exaggerate about how it 'spanks an M from 0-60' by 0.2 seconds :roll: As for how quick it can go round a track I couIdn't care less. If I wanted a track car it certainly wouldn't be an E89, unless the track was Santa Pod :poke:
Except for the fact that the Z4M coupe pulled in a 0-60 of 4.9s (road and track) where as the 35is is 4.4s (car and driver 2011)

0-100 the z4m coupe is 12.3s vs 10.7s of the 35is.

1/4 mile time of 13.6s vs 13.1s

Thats a pretty big difference......

willgill
Member
Member
Posts: 403
Joined: Tue Jul 16, 2013 10:58 am
Location: Cornwall

Why does the 35is speedo stop at 160mph?

Post by willgill » Thu Jul 20, 2017 8:46 am

Never let the truth get in the way of a good story :P
Image

User avatar
Pastry
Senior Member
Senior Member
Posts: 2288
Joined: Wed May 25, 2016 5:01 pm
Location: South East

Why does the 35is speedo stop at 160mph?

Post by Pastry » Thu Jul 20, 2017 9:01 am

sunnydays wrote: Thu Jul 20, 2017 8:37 am
Pastry wrote: Thu Jul 20, 2017 7:13 am
sunnydays wrote: Wed Jul 19, 2017 11:33 pm

Im not refuting how the car feels to drive. I am simply refuting people saying it is a poor handling car :). The fact it beats the M around the track speaks volumes
People exaggerate about its poor handling, just like you exaggerate about how it 'spanks an M from 0-60' by 0.2 seconds :roll: As for how quick it can go round a track I couIdn't care less. If I wanted a track car it certainly wouldn't be an E89, unless the track was Santa Pod :poke:
Except for the fact that the Z4M coupe pulled in a 0-60 of 4.9s (road and track) where as the 35is is 4.4s (car and driver 2011)

0-100 the z4m coupe is 12.3s vs 10.7s of the 35is.

1/4 mile time of 13.6s vs 13.1s

Thats a pretty big difference......
If it makes you feel great about your car....then fill your boots :lol:
991 Carrera 2S
Now gone:
2008 Z4MR Midnight Blue Metallic
2006 Z4 3.0si sport Ruby Black
2006 Z4 3.0si sport Titanium Silver
2010 Z4 23i Msport and a 3.0i

User avatar
sunnydays
Member
Member
Posts: 983
Joined: Fri Sep 23, 2016 7:50 am

Why does the 35is speedo stop at 160mph?

Post by sunnydays » Thu Jul 20, 2017 9:15 am

buzyg wrote: Thu Jul 20, 2017 12:07 am
sunnydays wrote: Wed Jul 19, 2017 10:55 pm
buzyg wrote: Wed Jul 19, 2017 6:38 pm

Could you kindly show me some physics, or some official proven figures please. The physics I was taught say it's unlikely.
My calculations based off
Drag coefficient of 0.34
1.96m sqd area
3500lb kerb weight
340 bhp

Gives a theoretical max of 185mph...

One thing you have not accounted for is the under rating of the N54 engines, it was proven that the N54 turbos put out approx 20-30bhp more than factory figures. BMW has done the same on some other turbo engines ie the M4

There is a 35is delimited with a slight tune comfortably hitting 190mph on youtube measured via GPS. Video below.....

What has kerb weight to do with it? :? Also be sure you are using the power at the wheels and not at the crank. Other wise the figures would suggest a Z4M can do 185mph also and it simply can not. That was my point. The two cars will have very similar unlimited top speeds, as they have similar power, similar cd figures and similar frontal area and the Z4m's is around 171mph.
Weight of the car affects the bhp required to hit a certain speed.

You are right my mistake! I have recalculated assuming a 15% drive terrain loss from 335bhp to 284bhp at the wheels. Using this figure the top speed now comes out at 175mph.

How far the N54 is underrated from the factory is going to make a difference here

Edit: just found a technical document from BMW stating the power is infact 340hp so accounting for this it takes the theoretical max to 177mph at stock
Last edited by sunnydays on Thu Jul 20, 2017 9:29 am, edited 1 time in total.

User avatar
sunnydays
Member
Member
Posts: 983
Joined: Fri Sep 23, 2016 7:50 am

Why does the 35is speedo stop at 160mph?

Post by sunnydays » Thu Jul 20, 2017 9:26 am

buzyg wrote: Wed Jul 19, 2017 11:57 pm Does any one have the gear ratios for a 35is? Including the final drive. I can't find them. :(
Found them :)

4.780
3.056
2.153
1.678
1.390
1.203
1.000
Final drive: 2.563

User avatar
Bing
Legend
Legend
Posts: 26514
Joined: Sun Oct 02, 2011 7:19 pm
Location: Exiled Scot in Maidstone

Why does the 35is speedo stop at 160mph?

Post by Bing » Thu Jul 20, 2017 9:27 am

I bet if you put two average to semi-decent drivers from this forum next to each other in a manual Z4M and a manual 35is and set them off on a drag race then there would be f**k all in it... Oh wait, the 35is doesn't come in manual right ? Which probably means that time difference is due to electronic reactions and control being superior to human manual input. Which is fine, and I have no problem with by the way. But tbh, reducing these cars to top speeds and straight line performance times completely misses the point of them, especially given that most will never vmax the car, or actually be able to match the manufacturer quoted acceleration times.

Personally that 0.5 sec difference means nothing to me because by 4.4 secs I am already having waaaaay to much fun for it to be legal :lol:
Current... Silver Grey ///M Roadster, non-flimper spec, Imola Red nappa, permanent ear-to-ear grin 8)

Previous... 3.0Si Sport Roadster, Black Sapphire, Dream Red leather with lots of toys and lots of mods...

User avatar
sunnydays
Member
Member
Posts: 983
Joined: Fri Sep 23, 2016 7:50 am

Why does the 35is speedo stop at 160mph?

Post by sunnydays » Thu Jul 20, 2017 9:38 am

Bing wrote: Thu Jul 20, 2017 9:27 am I bet if you put two average to semi-decent drivers from this forum next to each other in a manual Z4M and a manual 35is and set them off on a drag race then there would be f**k all in it... Oh wait, the 35is doesn't come in manual right ? Which probably means that time difference is due to electronic reactions and control being superior to human manual input. Which is fine, and I have no problem with by the way. But tbh, reducing these cars to top speeds and straight line performance times completely misses the point of them, especially given that most will never vmax the car, or actually be able to match the manufacturer quoted acceleration times.

Personally that 0.5 sec difference means nothing to me because by 4.4 secs I am already having waaaaay to much fun for it to be legal :lol:
Perhaps not in the Z4M but in the 35is you can utilise launch control as seen below. The manufacturer claim is 4.8s, independant magazine tests put it around 4.4.s.

The video below shows a real world 4.79s


The Z4M would be more difficult due to being manual, and lacking launch control

Pbondar

Why does the 35is speedo stop at 160mph?

Post by Pbondar » Thu Jul 20, 2017 4:54 pm

A bit of Googling gives:

Model BHP Top Speed Acceleration Torque NM
1.8i 153 137 7.8 240
2.0i 181 145 6.7 270
2.3i 201 149 7.1 250
2.8i 241 152 5.3 350
3.0i 254 157 5.9 310
PB Z4 280 160 5.2 380 (computed)
3.5i 301 167 4.9 400
3.5iS 335 173 4.6 450

Enjoy!

Excuse the formatting sure to provoke a storm..


Z4 numbers.jpg
Z4 numbers.jpg (38.53 KiB) Viewed 759 times

User avatar
Nanu
Lifer
Lifer
Posts: 3912
Joined: Mon Dec 03, 2012 4:47 pm
Location: Sunderland

Why does the 35is speedo stop at 160mph?

Post by Nanu » Thu Jul 20, 2017 7:59 pm

sunnydays wrote: Wed Jul 19, 2017 10:55 pm
buzyg wrote: Wed Jul 19, 2017 6:38 pm
sunnydays wrote: Wed Jul 19, 2017 6:32 pm


Torque, weight, gear ratios, tyres, downforce.

Considering the 35is spanks the Z4M from 0-60, 0-100 etc.... its not surpising it has a higher top speed
Could you kindly show me some physics, or some official proven figures please. The physics I was taught say it's unlikely.
My calculations based off
Drag coefficient of 0.34
1.96m sqd area
3500lb kerb weight
340 bhp

Gives a theoretical max of 185mph...

One thing you have not accounted for is the under rating of the N54 engines, it was proven that the N54 turbos put out approx 20-30bhp more than factory figures. BMW has done the same on some other turbo engines ie the M4

There is a 35is delimited with a slight tune comfortably hitting 190mph on youtube measured via GPS. Video below.....

The fact that in this video they are indicating left and right at those speeds evidences the good handling in my book :rofl:
G29 M30i M Sport San Francisco Red

Previous
E89 35is Valencia Orange
E89 28i Crimson
E89 25i White

User avatar
sunnydays
Member
Member
Posts: 983
Joined: Fri Sep 23, 2016 7:50 am

Why does the 35is speedo stop at 160mph?

Post by sunnydays » Thu Jul 20, 2017 11:36 pm

Pbondar wrote: Thu Jul 20, 2017 4:54 pm A bit of Googling gives:

Model BHP Top Speed Acceleration Torque NM
1.8i 153 137 7.8 240
2.0i 181 145 6.7 270
2.3i 201 149 7.1 250
2.8i 241 152 5.3 350
3.0i 254 157 5.9 310
PB Z4 280 160 5.2 380 (computed)
3.5i 301 167 4.9 400
3.5iS 335 173 4.6 450

Enjoy!

Excuse the formatting sure to provoke a storm..



Z4 numbers.jpg
Very nice, so much for the 35is wont break 160 crew..........

User avatar
buzyg
Legend
Legend
Posts: 26423
Joined: Fri May 20, 2011 6:11 pm
Location: Cornwall

Why does the 35is speedo stop at 160mph?

Post by buzyg » Fri Jul 21, 2017 12:08 am

Pbondar wrote: Thu Jul 20, 2017 4:54 pm A bit of Googling gives:

Model BHP Top Speed Acceleration Torque NM
1.8i 153 137 7.8 240
2.0i 181 145 6.7 270
2.3i 201 149 7.1 250
2.8i 241 152 5.3 350
3.0i 254 157 5.9 310
PB Z4 280 160 5.2 380 (computed)
3.5i 301 167 4.9 400
3.5iS 335 173 4.6 450

Enjoy!

Excuse the formatting sure to provoke a storm..



Z4 numbers.jpg
Now those figures look far more realistic. :thumbsup:
Image

Post Reply