Theoretical top speed of Z4M?

[Serious]

I promise you a stock MZ4 with the limiter removed will hit 170mph. My e46 m3 was nudging it without even trying.

[Caddyshk]

On stock tires in OE trim the first owners using GPS reported 165-167mph in 5th at redline on the limiter. I seem to recall unlimited cars in Europe in the 171-173 range in 6th...

[MIKe86]

Originally Posted by Serious

I promise you a stock MZ4 with the limiter removed will hit 170mph. My e46 m3 was nudging it without even trying.

Originally Posted by Caddyshk

On stock tires in OE trim the first owners using GPS reported 165-167mph in 5th at redline on the limiter. I seem to recall unlimited cars in Europe in the 171-173 range in 6th...

Fair enough. I'm not going to get into what I've seen on my dashboard on here, but I will say it'll take a decent sized stretch of road to see that 170.


BTW, if I remember correctly off a coefficient of drag chart i saw a while back - your e46 m3 is more aerodynamic than our z4mc's

[Dammmittt]

Originally Posted by pokeybritches

There is no limiter in 5th. That's a fact.

That's not a fact. Here's the info you're looking for.
http://www.bimmerfest.com/forums/sho...p+speed&page=3

I'll tell you that a top speed in the 170's is probably accurate. I hit 160 indicated several times yesterday but I didn't have enough space to go much faster.

[Leo_328i]

I own a Z4 M Roadster which I purchased in the UK whilst I was living there.

My car had oversized rear tyres on it (255/40/18 as opposed to the usual 255/35/18) and I was able to hit the speed limiter which cut in at 263km/h with the roof down and both windows fully up in 6th gear.

I found that I hit the rev limiter in 5th gear (stock ECU) before hitting the top speed limiter. The S54 seems to 'soft cut' at 8000rpm in higher gears which feels very different to hitting the speed limiter. When you hit the speed limiter, it feels almost like someone has just yanked the handbrake, you loose throttle and about 5-10km/h or so before throttle is re-engaged.

It was still pulling slowly at that speed.

I never did a top speed run with the roof on as the wind seepage past the window seals was annoying at speeds above 130km/h and unbearably annoying by 180km/h.

Besides tyre size and an aftermarket panel filter, the car was completely stock and also fully loaded with a few months worth of luggage in the boot. Keep in mind its a Euro spec car with the proper headers.

This is me cruising around in Germany at close to top speed:

Edit: One additional point worth mentioning is that I changed my front tyres half-way during my time in Germany from 225/45/18s to 225/40/18s and noticed the car significantly less stable at speeds above 220km/h. It wasn't any fault of the tyre not doing its intended job (Michelin Pilot SS) - but I believe the extra area or volume within the wheel well with the smaller-sized tyre causes the front of the car to lift more at high speed.

[DVCNick]

Basically at the end of the day it comes down to drag vs. power (assuming no governor of course). You stop accelerating when the sum of the drag forces pushing the car back equals the power pushing the car forward. Most any car I'm aware of today runs out of power before it runs out of gear.

Falling-out-of-an-airplane terminal velocity has nothing to do with it, as gravity doesn't make the same power as the motor, and the drag characteristics will change drastically as the car's attitude in the air would not be constant. Even in the lower atmosphere I think the car would fall a whole lot faster than the motor can push it across the ground. Gravity is no joke.

I've only had my car a short time, but I've noticed the speedo reads way high, like 5-6 mph at an indicated 80. If the governor is based on the speedo reading (I don't know if it is) my car, at least, would actually be limited to something significantly below 155. On the way home I got some open space, and I didn't get that high, but it was still pulling very strong with lots of RPM left in 5th, so I don't think it would have any issues getting to a 155 governor pretty quick and bounce right off. My Kentucky windage guess based on the stats I see would be somewhere around 170ish unlimited. I might be scared to really try it in a roadster though.

[mmm-five]

Originally Posted by Leo_328i

My car had oversized rear tyres on it (255/40/18 as opposed to the usual 255/35/18)

They're not oversize. 255/40r18 are the stock size on an M. 255/35r18 are stock 18" tyre size on the non-Ms.

Mine is running 265/40r18 which brings the speedo more in line with the real speed.

On mine, 5th delivers 175mph speedo/171mph GPS (at normal rev limit), 6th only delivers 161mph speedo/157mph on GPS, due to the lower soft rev limit).

[53Fatman]

I think this one could have done 280-285kmh. 278kmh = 173mph

It has slightly more Power (370PS) and no limiter

[FD3S]

Originally Posted by 53Fatman

I think this one could have done 280-285kmh. 278kmh = 173mph

It has slightly more Power (370PS) and no limiter

What mods do you have Fatman for the 370 PS ?

[53Fatman]

Sorry, its not my car, but he says its only exhaust and an individual tune. (video description).

If it was mine i would have pressed the accelerator down till top speed

[garz747]

Its sadly a moot point here in Ontario Canada where you are charged with "racing" if clocked at 50km over the speed limit (31mph) Car is seized and possible $5000 fine too! Murderers are treated more fairly lol. Still those speeds mentioned are damn impressive for a naturally aspirated sweet six- even in this day and age.

[RABAUKE]

I'm going to say 195mph, dragged behind one of those sexy Tesla Trucks.

[mmm-five]

Originally Posted by RABAUKE

I'm going to say 195mph, dragged behind one of those sexy Tesla Trucks.

Or a high percentage of the speed of light if dropped in the vicinity of a black hole

[WeekendWarriorz]

I've had mine up to 175-180ish, wish I could've pushed it faster but ran out of road.