How fast will a Z4 actually go?

[20ducks]

Been there....many many times. Just wanted to make sure.

 

[Zeefour]

limited to 135 here in the States. There is a youtube of someone hitting 160 mph on the autobahn. I have no idea if they've reached the rev limiter or if they've just milked all out of the stock intake/exhaust, etc they can. I'm sure if you let someone like DINAN get hold of it, it may go a bit faster.

Not model year 03, had mine a tad bit over 140 mph :driving:

 

[Smokin]

limited to 135 here in the States. There is a youtube of someone hitting 160 mph on the autobahn. I have no idea if they've reached the rev limiter or if they've just milked all out of the stock intake/exhaust, etc they can. I'm sure if you let someone like DINAN get hold of it, it may go a bit faster.

Not model year 03, had mine a tad bit over 140 mph :driving:

I corrected my post--it's 155 for the 3.0Si.....still, 140 is impressive out of a inline 6 cylinder engine.

 

[Jas667]

Jas667: was that in 5th or 6th gear?

If Im being honest I cant remember but I think it was 6th

 

[DaveZ4C]

OK,

Reading through all the replys, observations, calculations, graphs, this is what I'm hearing,

The Z4 Coupe 3.0 si sport should do around 165mph.
The Z4 Coupe 3.2 M should do around 180mph
The Z4 2.5i should do around 145mph

What I heard was,

Z4C 3.0 - 165mph
The Z4C 3.0 is limited to 155mph in Europe and 135mph in some parts of the US

Someone has had it to 163mph and accelerating (measured by GPS). My very scientific graph suggests 165mph, which seems consistent with the observed 163mph+ figure

The car would do 187mph if there was no air resistance (ie. in a vacuum) but the driver would probably have died by then and the fuel wouldn't burn in the engine.

Z4MC - 180mph
The Z4MC is limited to 155mph in Europe. Someone believes that their M is limited to 168mph (USA?).

Someone has had it to 180mph (measured by speedo?). My very scientific graph suggests 177mph, which seems consistent with the observed 180mph figure.

The car would do 197mph if there was no air resistance (ie. in a vacuum) if it was driven by a robot and had air injected into the cylinders.

Z4 2.5i - 245mph
Someone has had the 2.5i to 144mph (measured by speedo?). My very scientific graph suggests 146mph, which seems consistent with the observed 144mph figure.

If all of these observations are failrly consistent with my very scientific graph (VSG) then the 2.5si shold do around 155mph

Think I'll become a scientist.

Dave

 

[Smokin]

I am a scientist and you've done a darn good job of it.

Did you graph curves or bars? I'll have to play with Excel this weekend.

 

[20ducks]

I worked on curves in bars, does that count for anything?

 

[2dogs]

I am a scientist and you've done a darn good job of it.

Did you graph curves or bars? I'll have to play with Excel this weekend.

Sounds like a ripping weekend. oke:

 

[Top pup]

Z4 2.5i - 245mph

 

[DaveZ4C]

Z4 2.5i - 245mph

You see, that's why I'm not a scientist. I make typing errors.

I meant that the 2.5i will do 145,000mph

Dave

 

[DaveZ4C]

I am a scientist and you've done a darn good job of it.

Did you graph curves or bars? I'll have to play with Excel this weekend.

I put the figures into Excel and did an x,y scatter with a line through it and it drew a nice curve. I then called it the VSG (very scientific graph) to give it added credibility.

Dave

 

[Smokin]

Did you get the standard error of the mean and go +/- 2 sd? :wink:

 

[DaveZ4C]

Did you get the standard error of the mean and go +/- 2 sd? :wink:

No, I used a thick crayon.

 

[Smokin]

Actually , that only took a minute. Interesting part of the graph is noting the great increase in horsepower but a much smaller increase in speed. Are any of these other machines electronically limited and are the mph numbers the theoretical top speed? I'll have to expand the x axis a bit to see exactly where the Z fits but it does look very close.

 

[Top pup]

Z4 2.5i - 245mph

You see, that's why I'm not a scientist. I make typing errors.

I meant that the 2.5i will do 145,000mph

Dave

Being fair your other figures do seem about right to me

 

[DaveZ4C]

Actually , that only took a minute. Interesting part of the graph is noting the great increase in horsepower but a much smaller increase in speed. Are any of these other machines electronically limited and are the mph numbers the theoretical top speed? I'll have to expand the x axis a bit to see exactly where the Z fits but it does look very close.

I only used cars that are not limited/restricted.

 

[DaveZ4C]

Being fair your other figures do seem about right to me [/quote]


I like to think of them as very scientific

 

[Smokin]

Actually , that only took a minute. Interesting part of the graph is noting the great increase in horsepower but a much smaller increase in speed. Are any of these other machines electronically limited and are the mph numbers the theoretical top speed? I'll have to expand the x axis a bit to see exactly where the Z fits but it does look very close.

I only used cars that are not limited/restricted.

Then the change in the slopes for increase in bhp and increase in top speed are even more interesting.

 

[DaveZ4C]

Didn't someone say that wind resistance increases exponetially with speed?

This would mean, for example, that at 150mph you need much more power to get a 10mph increase in speed than you would at 100mph.

This would cause the curve.

 

[DaveZ4C]

To go any faster, you would need much more horsepower (Bugatti Veyron 1000+ bhp) and/or a change in aerodynamics, ie. move from a coupe shape to a race-car shape (ferarri, lambo, robin reliant).

Dave