View Full Version : top speed
Ian Thu, Aug-30-2001, 06:22:00 PM I ran top speed on my car last week, and the "soft" limiter kicked in at an indicated 170 mph. I also used my gps to verify speedo error and at 100 mph indicated the gps read 95 actual mph. Assuming the 5% error is the same at 170 indicated, this means i achieved a true 161.5 mph. Higher than the 155 mph limiter the car was to be limited at. Interesting note, the car pulls max hp at 7900 rpm which equals an indicted 210 mph minus the 5% speedo error, which is an actual 199 mph. Now i know the car will never pull a true 199 mph, but i think a true 180 mph is certainly possible?
Frank Thu, Aug-30-2001, 10:09:00 PM Whoa! That's FAST! Where did you make the run???
I have heard that BMW's speedo is optimistic by about 5-10mph. I can't imagine this car pulling to 180 mph with the aerodynamics of the car. The C5 vette which has 345 hp, is quite a bit lighter, and has a much more aerodynamic body might hit 180 I think.
I dont really know; I have never run my car that fast. The fastest I've ever gone in one of my cars is around 160 in the vette and it was VERY VERY scary! Felt like there was more but didnt feel comfortable pushing it any faster.
How did the M3 feel at that speed? Was it stable? The car is so sensitive to even slightest cambers in the road that I would think it was fairly busy at that speed.
161.5 mph...YOU'RE THE MAN! http://m3forum.com/ubb/smile.gif
Be careful and happy motoring!
Ian Fri, Aug-31-2001, 11:48:00 AM Frank: the car felt pretty solid, but you had to pay attention. I am used to going fast on motorcycles and a car requires more attention at that speed than a bike. I have actually been 212 mph Indicated (about 192 true speed) down the same deserted 3 mile straight, with no intersections, in Florida.
It was a lot of fun, and i look forward to removing the speed limiter for an unlimited run.... http://m3forum.com/ubb/smile.gif
dlubbers Sun, Sep-09-2001, 02:08:00 PM I just got back from a little Sunday cruse. I was about 60 miles west of Houston and came
across a nice stretch of I-10 east and decided to see where the top end of my new M3 could
be found. Located on my dash, both a Garmin StreetPilot III GPS connected to all 12
satellites and a Radar detector. :^)
A couple of thoughts... The workload at the top end increases significantly. I didn't have to
fight Gunther but you have to DRIVE THE CAR. Things happen at a much faster rate. I
always thought the car driving video games exaggerated the effects of speed but I'm not so
sure any more! I was just passing through 6500 RPM and making good power when the ECM
said that's it. My GPS read max. speed 162 M.P.H. The motor just quit making power and it
was noticable. Gunther was pulling like a big dog right up to the 162 M.P.H. mark.
Anybody heard when the software without the top speed governor is going to be available?
Frank Sun, Sep-09-2001, 05:07:00 PM I guess the top speed governor must be rpm based (6500rpm in 6th gear?). This was probably stupid, but I always thought it was speed based...i.e top speed governed at 155mph, etc.
Do you know what your speedo was showing at the time? did it agree with the GPS?
Off topic, my favorite video driving game is NFS: Porsche Unleashed. I tried playing some of the other NFS games after playing the NFS:PU (which has '4 point' physics) and they "felt" like video games. The Boxster in the game drives very very similar to the real thing in terms of its handling. I wish they would come out with a similar game for BMW's...could be called NFS: M Power Unleashed. http://m3forum.com/ubb/smile.gif
dlubbers Sun, Sep-09-2001, 06:21:00 PM I'm not sure what the speedo was reading... I was so busy driving I didn't have time to look at it. I'm not sure if the top speed governor is MPH or RPM based. I couldn't get over 6500 RPM in 5th gear on the dyno last week and I thought maybe it was RPM based so I decided to see if I could get over 6500 RPM in 5th. I shifted at 7200 RPM into 6th. I can go over 6500 RPM in 5th so the dyno problem is not the governor at 6500 RPM. Next weekend I'm going to see where 5th gear will take me. I'll also keep an eye on the speedo....
Guest Wed, Oct-03-2001, 04:22:00 AM greta stories i had my M3 speedo at 170 myself and the car felt damn stable to me i switched lanes with no problem. I had 19 inch rims though but the Gps read 161.2 the thing is i just had put it in 6th i bet my life on it this car can almost hit 180 easy with no limiter. A company in germany claims they hit 197 in theirs. i think its possible
Ian Wed, Oct-03-2001, 02:12:00 PM I used my GPS a few weeks ago and the car ran 162.3 mph @ 6500 rpm in 6th gear. An interesting note is that i made the run again in 5th gear and it ran the SAME speed but was very near red line! The limiter is obviously in 6th gear and not in 5th, but max hp in 5th stops you from going any faster. If someone was really into going faster before the speed limiter remover was available, they could change the gearing and allow the car to go a lot faster in 5th.
RLJ Tue, Aug-26-2003, 05:52:46 AM Just to weigh in with an additional data point - Had my '03 out for a late-night run for the limit. I hit an indicated 170 and had to back off due to a couple of cars on the road ahead. I didn't hit the limiter, but did not push through 170 so it may have been there as it was for others. With 19" tires the M3 has an indicated speed error of slightly less than 5%, according to the GPS, giving me a true speed of about 161.5 - again confirming the experience of others.
The car was extremely stable, but required complete focus as it's normal responsiveness to steering input was magnified by the speed. When crossing lanes the tires wanted to track the lane divider "turtles" and required both hands and a firm grip to cross smoothly.
If the limiter can eventually be removed at a reasonable price I might do it (for some reason I can't really justify). But frankly, through the windshield little things grow big plenty damn fast at 161.5 and I don't expect to spend much time there.
Beowoulf Tue, Aug-26-2003, 06:53:42 AM Couple of facts for you guys.
The speed limiter can be easily removed with an aftermarket reprogram of the ECU. Without limiter you can do about 168 if I'm not mistaken. Do a search.
The speedo is off by about 6+% making 170 indicated to be about 158-159.
The aerodynamics of the M3 play a great role in the top speed. The fasted I have seen is about 189mph with a turbo engine.
Tico Tue, Aug-26-2003, 01:56:25 PM Ian,
Is that 3-mile stretch off of I-4 in Polk County? That's where I used to unleash my '02 ZX-12R. When I finally take delivery of my M3 (around mid October) I plan to do some of the break-in on that stretch of road.
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