Restricted Speed on the Z4

[Frankbrot]

I am the happy owner of a 2011 SDrive35is, but I must admit that it really bothers me that the car has more speed and power that I can't access. Can anyone tell me why BMW restricts the top speed on this otherwise wonderful car? Can you remove the restriction and replace the speedometer?? How? Will that void the warranty? Thanks for anyone's response.

Frank

[persian54]

BMS has a thing for the regular N54, I think it might work for the iS

Yes it would void warranty

You can prly do Dinan too


if you noticed, most German cars are pretty much limited to 155

[marcw]

There are two main reasons why most German car manufacturers limit top speed to 155mph. It's a self imposed limit by the car industry much like the MPAA rating for movies. There has been a long ongoing debate within Germany to limit top speed to 130 km/h (85mph). At various times politicians have tried (and failed) to impose overall speed limits. The move from the manufacturers to impose a self imposed limit was to stall attempts from the government to impose a limit by law. The other reason is that tires which can withstand such speeds become rarer and rarer the higher up the speed ladder you climb. It was seen as a liability to the car industry to let people drive well beyond the 155mph mark. Of course car manufacturers are well aware that it isn't exactly rocket science to remove the limiter. As a matter of fact in Germany you can now pay extra and BMW will not put in a limiter for any M model car.

[Memphis1]

Sorry marcw, not entirely true.

The speed limit of 155mph or 250kph, is the limit at which other components can withstand being pushed for an extended period of time. think about it in terms of the bugatti, the gasoline runs out in 12 mins at top speed because the tires will give out at 15mins. so it's a way of making sure your car lasts a good length of time because they know the consumer will be at risk and or doesn't have the budget like an F1 team to use an engine per race or three sets of tires per day.

[BlueZ4AZ]

I too, find myself frustrated that I cannot go faster than 135 mph on any of our 65 - 75 Speed Limit highways here in AZ.
I enjoy the exhilarating feeling of risking my life and the possibility of a night in jail.

[Silver-Bolt]

Most of the software (aftermarket) upgrades have the ability to remove the speed limiter. The limiter is software only meaning that no parts have to be changed. With no limiter the top speed is in the 175-180mph range. Alabama must have some very forgiving speed laws.

[Mr. ///M3 RD]

Any one that is not happy with a 150 MPH or 155 MPH top speed on a sports / street car should IMO get himself a plane and fly real close to the ground since if you fly high as you know you still move real slow ...

All fun to the side, if anyone needs a faster car then by all means build one and get a trailer to tow it to a track ... only keep it off the public roads. I am sure that is what Frank has in mind I hope.

[Mr. ///M3 RD]

Originally Posted by BlueZ4AZ

I too, find myself frustrated that I cannot go faster than 135 mph on any of our 65 - 75 Speed Limit highways here in AZ.
I enjoy the exhilarating feeling of risking my life and the possibility of a night in jail.

making a note to bypass Arizona next time I head out west

[BlueZ4AZ]

Originally Posted by Rolf-Dieter

making a note to bypass Arizona next time I head out west

We got a pretty tough Sheriff out in these here parts too.

[Mr. ///M3 RD]

Originally Posted by Memphis1

Sorry marcw, not entirely true.

The speed limit of 155mph or 250kph, is the limit at which other components can withstand being pushed for an extended period of time. think about it in terms of the bugatti, the gasoline runs out in 12 mins at top speed because the tires will give out at 15mins. so it's a way of making sure your car lasts a good length of time because they know the consumer will be at risk and or doesn't have the budget like an F1 team to use an engine per race or three sets of tires per day.

+1

[Mr. ///M3 RD]

Originally Posted by BlueZ4AZ

We got a pretty tough Sheriff out in these here parts too.

Yes I know, he could not catch me last August I was too fast for him he gave up Hahahaha

[Mr. ///M3 RD]

Originally Posted by Silver-Bolt

Most of the software (aftermarket) upgrades have the ability to remove the speed limiter. The limiter is software only meaning that no parts have to be changed. With no limiter the top speed is in the 175-180mph range. Alabama must have some very forgiving speed laws.

Alabama Speed Limits

In Alabama, trucks carrying hazardous materials are not to exceed 55 mph. A speed limit of 30 mph in urban areas and 35 mph on unpaved rural roads is enforced. The speed limit for county paved roads is 45 mph. All other 2 lane roads are limited to 55 mph. The interstate limit is 70 mph while other 4 lane highways are limited to 65 mph.

[Vintage]

I have done 165 indicated in my 2001 M Coupe after I had the limiter removed. Scared the ___________ out of me and I said to myself - no need to do that crazy crap again. 120 is plenty and I would do that only on a track (we also did about 110 on the autobahn at our ED a year ago August, very fast but not too crazy)

[cdeslandes]

Originally Posted by Memphis1

Sorry marcw, not entirely true.

The speed limit of 155mph or 250kph, is the limit at which other components can withstand being pushed for an extended period of time. think about it in terms of the bugatti, the gasoline runs out in 12 mins at top speed because the tires will give out at 15mins. so it's a way of making sure your car lasts a good length of time because they know the consumer will be at risk and or doesn't have the budget like an F1 team to use an engine per race or three sets of tires per day.

You, Sir, are correct.

Like any manufacturer, BMW has to make decisions based on cost. That includes potential litigation, especially in the U.S.

In the USA, the Z4 is limited to 130 mph without the sport package. This allows BMW to fit V-rated tires, which have a top speed of 149 mph, on its base 17" wheels.

With the ports package, the limited is set at 155 mph, and W-rated tires (good for up to 168 mph) are used.

Many manufacturers follow the 155 mph guideline for European models, lower settings in North America, and no limiter in the Middle East (for those crazy speed runs in the desert!)

[Mr. ///M3 RD]

Originally Posted by VintageBMW

I have done 165 indicated in my 2001 M Coupe after I had the limiter removed. Scared the ___________ out of me and I said to myself - no need to do that crazy crap again. 120 is plenty and I would do that only on a track (we also did about 110 on the autobahn at our ED a year ago August, very fast but not too crazy)

Some years ago (must be 20 years now) I drove north in one of the US states and a little Fiat speed by me like he was on fire. I stopped for lunch and told the waitress about it. She told me "Why there are no speed limits in our state" The Poolice (spoken in her accent) will only stop you if you are driving fast in a car that is considered not safe"

Well after lunch I got into my 1987 Mercedes 300 AMG and gave her the gun, got her up to around 280 KM (174 MPH) it felt like I was about to take off and fly .... yes it was scary. I think that was the fastest I ever traveled on the ground

This photo shows my then MG in the background, the 535is I still have and it can fly My Benz traveled coast to coast with me as did my 1987 525is

[cdeslandes]

Originally Posted by Rolf-Dieter

Some years ago (must be 20 years now) I drove north in one of the US states and a little Fiat speed by me like he was on fire. I stopped for lunch and told the waitress about it. She told me "Why there are no speed limits in our state" The Poolice (spoken in her accent) will only stop you if you are driving fast in a car that is considered not safe"

Well after lunch I got into my 1987 Mercedes 300 AMG and gave her the gun, got her up to around 280 KM (174 MPH) it felt like I was about to take off and fly .... yes it was scary. I think that was the fastest I ever traveled on the ground

You must have been in Montana.

[Mr. ///M3 RD]

[QUOTE=cdeslandes;8112716]You must have been in Montana.[/QUOTE

yes that is correct going straight north

[Rafale]

A little different but the Maglev train in Shanghai is pretty exhilarating: 420km/h! It's pretty impressive when the cars the train passes on the highway feel like they are at a standstill at 120km/h.

[mcbeee]

I hit the limiter in the Z4 before I got the Dinan installed but haven't found a road in good enough condition to try it without the limiter ie: smooth with no access roads and clear of traffic for the 2 miles it takes to get it up there and back down again. You'd be amazed at how much pavement goes by at 160 when you are looking for that last 20mph.
Stopping also takes a bit if you don't want to cook the brakes.....jam on the brakes at 160 and you think you've slowed down a lot until you read the speedo and see you're still doing aver 120 !!!!

[Silver-Bolt]

191 mph on a motorcycle is my top to date. I want to crack 200 mph on a bike and also a car in the near future. Not on an open road though. Head to Nevada for the Silver State Classic. See how fast you can cover to 100 mile section of closed road. I rode shotgun and navigated for a buddy. We averaged right at 160 mph (in a pick up truck lol). I would much rather have been behind the wheel.

http://www.sscc.us/

[Mr. ///M3 RD]

you Fellows might enjoy this

It is in German, however, as the saying goes a picture is worth a 1000 words. That being said there are many pictures

At first when he checks it out (in the beginning) he checks out by foot the black stripes 1st, 2nd and 3rd gear total length about 1/2 KM

It has 800 HP under the bonnet.

This M6 will go from 0 to 300 KM in 26 Seconds

In the end on the Autobahn he takes her to 300 KM/H and has fun with a Porsche

Now if only gas was not so expensive it be a fun car ... oh wait then there is the price of the car ... we don't talk about that do we now

Enjoy the video

Click here for the YouTube Video

[rmorin49]

You folks need to do an European Delivery! I drove my E93 with the top down at 145 mph and I can tell you it was exhilarating. That said, while the car seemed pretty stable it was very nerve wracking. I stayed in the left lane for a while but had to move over several times for a couple Porsches and Benzes. Slowing down to around 125 seemed much more comfortable.