I like to fool around with data and produce graphs to see if anything interesting catches my eye, and I was doing this with some recent DSG Octavias.

As you can see, there's a discrepancy for the 245PS vRS's top speed because of the 155MPH speed limiter.

Does anyone know what the top speed of a 245PS vRS is *without* the speed limiter?

Any guesses?

 

 

 

Looking at some other vRS top speeds, I'm not sure it's much of a discrepancy.

The 220vRS max speed is quoted as 154MPH (pre FL model) with the 230vRS at 155MPH.

I'm guessing the 245PS vRS true top speed is probably in the range 156-158.

(It seems a bit pointless to limit it, unless there is legislation or a technical requirement to limit it it.

After a quick online search it seems there are a few theories about the 155 limit.

1) The "It's my understanding that there was a gentleman's agreement..." theory, which sounds to me like an urban myth that gained traction.

2) The "It was to pacify the greens" theory, which doesn't ring quite true to me.

3) The "Things get really crazy after 155MPH and you need beefed-up car components" theory. This one sounds the most plausible to me.

 

51 minutes ago, EnterName said:

1) The "It's my understanding that there was a gentleman's agreement..." theory, which sounds to me like an urban myth that gained traction

I was working for a sports car manufacturer when the 155 limit was introduced and can confirm that it was a "Gentleman's Agreement" between most German car manufacturers and the German Government - this was shortly after German reunification and there had been a dramatic increase in the number of high speed accidents on unrestricted stretches of autobahn (drivers from the former East Germany had no experience of cars approaching at nearly 200mph so pulled out in front of them going much slower causing massive accidents).

35 minutes ago, PetrolDave said:

I was working for a sports car manufacturer when the 155 limit was introduced and can confirm that it was a "Gentleman's Agreement" between most German car manufacturers and the German Government - this was shortly after German reunification and there had been a dramatic increase in the number of high speed accidents on unrestricted stretches of autobahn (drivers from the former East Germany had no experience of cars approaching at nearly 200mph so pulled out in front of them going much slower causing massive accidents).

Thanks for the insider info.

I suppose the supercars that are *not* restricted to 155 are so few in number, that restricting their speeds would not dramatically reduce accidents.

Why 155 and not 150 though? Is it as simple as 250km/h is a nice round number?

 

It's a great nuisance to me being only able to do 155 through Germany as opposed to the full potential of....well, 158,  dramatically increasing my journey times to my bolthole in the Bavarian Alps....

 

Fraulein,   I will be there in a mo.....!

 

 

😉

52 minutes ago, PetrolDave said:

I was working for a sports car manufacturer when the 155 limit was introduced and can confirm that it was a "Gentleman's Agreement" between most German car manufacturers and the German Government - this was shortly after German reunification and there had been a dramatic increase in the number of high speed accidents on unrestricted stretches of autobahn (drivers from the former East Germany had no experience of cars approaching at nearly 200mph so pulled out in front of them going much slower causing massive accidents).

 

It was worse than that: There is a lot of truck traffic across Germany, and some Eastern European truck drivers (judging by their plates/truck branding, which may not be the full story), and some truck drivers seem to want to play some elaborate game, involving pulling out in front of fast cars. On a two lane autobahn, this is really dangerous.

7 minutes ago, Phil245 said:

It's a great nuisance to me being only able to do 155 through Germany as opposed to the full potential of....well, 158,  dramatically increasing my journey times to my bolthole in the Bavarian Alps....

 

Fraulein,   I will be there in a mo.....!

 

 

😉

There *was* method in my madness. 😛

I was trying to determine what power is required for a FL MKIII Octavia to reach 150MPH.

To do this, I was planning to use linear interpolation between an Octavia which does a little under 150, and one which does over 150. However the 155 speed is limited, which would make any calculation inaccurate.

Hence the original question.

 

I do not have any kind of reasonable explanation for why I wanted to know what power a FL MkIII needs to hit 150MPH, other than I didn't don't know.

 

Edited 25 July, 20205 yr by EnterName

3 minutes ago, EnterName said:

There *was* method in my madness. 😛

I was trying to determine what power is required for a FL MKIII Octavia to reach 150MPH.

To do this, I was planning to use linear interpolation between an Octavia which does a little under 150, and one which does over 150. However the 155 speed is limited, which would make any calculation inaccurate.

Hence the original question.

 

I do not have any kind of reasonable explanation for why I wanted to know what power a FL MkIII needs to hit 150MPH, other than I didn't don't know.

 

Well I have already done this experiment for you 6 years ago. Let me explain took my October 2013 Mk3 2.0 litre diesel Octavia to AmD in Essex 7 months after I bought it with 7,000 miles on the clock and after some ECU fettling it went from 147bhp and 246lb/ft on their rolling road to 186bhp and 317lb/ft. When it was standard it would hit the Skoda claimed maximum of 135mph yet with the extra 39bhp it managed 150mph, so there you go your answer.

5 minutes ago, shyVRS245 said:

Well I have already done this experiment for you 6 years ago. Let me explain took my October 2013 Mk3 2.0 litre diesel Octavia to AmD in Essex 7 months after I bought it with 7,000 miles on the clock and after some ECU fettling it went from 147bhp and 246lb/ft on their rolling road to 186bhp and 317lb/ft. When it was standard it would hit the Skoda claimed maximum of 135mph yet with the extra 39bhp it managed 150mph, so there you go your answer.

The pre FL model isn't a problem as the old 220PS MKIII was rated at an unlimited 154MPH, so could be used to accurately linearly interpolate. (Which I might do in a bit. How did you measure your 150MPH?)

However the FL MkIII has different front end (as well as other things I expect), which I can't rely on not to have affected the aerodynamics, which will in turn affect the top speed, especially at those speeds.

Edited 25 July, 20205 yr by EnterName

4 minutes ago, EnterName said:

The pre FL model isn't a problem as the old 220PS MKIII was rated at an unlimited 154MPH, so could be used to accurately linearly interpolate. (Which I might do in a bit. How did you measure your 150MPH?)

However the FL MkIII has different front end (as well as other things I expect), which I can't rely on not to have affected the aerodynamics, which will in turn affect the top speed, especially at those speeds.

What is the claimed top speed of your 190PS Octavia? Remember the Mk1 Vrs Octavia with just 177bhp back in 2003 could hit an official 146mph maximum and the Mk2 with 197bhp raised that to 152mph. The 150mph was from the Speedo which may have been optimistic TBH.

18 minutes ago, shyVRS245 said:

What is the claimed top speed of your 190PS Octavia? Remember the Mk1 Vrs Octavia with just 177bhp back in 2003 could hit an official 146mph maximum and the Mk2 with 197bhp raised that to 152mph. The 150mph was from the Speedo which may have been optimistic TBH.

Claimed top speed of my 190 is 147MPH, which I reckon is rounded one way or another.

 

Here are the MKIII pre facelift numbers I have. (The additional accuracy is presumably because the original source was in KMH. So these may be more accurate than the MPH numbers quoted in the UK, and I may need to revisit my MPH figures for the FL *assuming* the original data was in KMH and there are rounding errors in the conversion to MPH for the UK.  But I digress)

So this is ideal.

 

And the numbers look like this.

On the pre-FL MKIII, 210PS should be enough to crack 150MPH.

The formula I'm using is (Note that cell Q2 is Power 1 and cell Q6 is speed 2.)

 

Edited 25 July, 20205 yr by EnterName

19 minutes ago, shyVRS245 said:

What is the claimed top speed of your 190PS Octavia? Remember the Mk1 Vrs Octavia with just 177bhp back in 2003 could hit an official 146mph maximum and the Mk2 with 197bhp raised that to 152mph. The 150mph was from the Speedo which may have been optimistic TBH.

I doubt your speedo was spot on at 150MPH, but you never know.

The MK1 Octavia will have different aerodynamics again, not to mention the different weight of the car (which is also a significant factor between the MK2 and MK3, I believe.)

Its not a linear relationship and the gearing will play a large part in the max speed acheieved, I doubt that any of the vehicles will be at V max with the revs at the max power point.

 

Iffor example you have one vehicle 140 hp = 140mph top speed and the other 160hp = 160 top speed even if they were at the revs equating to peak power tuning an engine to produce 150 hp will result in less than 150mph top speed ignoring all the other variables.

 

I think the power required to overcome the wind and rolling resistance increases with the square of the increase in speed desired, it is probably a different exponential but definitely is not linear.

 

Its why no matter how much HP is thrown at a new supercar it will only go a little bit faster than the predecessor, to beat the current production car record speed (Bugatti Veyron?) is probably going to require a doubling of the horsepower requiring a much larger air intake making a larger frontal area and increased drag, future record holders will be electric powered and with very low CdA.

A members vid from a thread in the General Automotive chat. 

 

 

17 minutes ago, J.R. said:

Its not a linear relationship and the gearing will play a large part in the max speed acheieved, I doubt that any of the vehicles will be at V max with the revs at the max power point.

 

Iffor example you have one vehicle 140 hp = 140mph top speed and the other 160hp = 160 top speed even if they were at the revs equating to peak power tuning an engine to produce 150 hp will result in less than 150mph top speed ignoring all the other variables.

 

I think the power required to overcome the wind and rolling resistance increases with the square of the increase in speed desired, it is probably a different exponential but definitely is not linear.

 

Its why no matter how much HP is thrown at a new supercar it will only go a little bit faster than the predecessor, to beat the current production car record speed (Bugatti Veyron?) is probably going to require a doubling of the horsepower requiring a much larger air intake making a larger frontal area and increased drag, future record holders will be electric powered and with very low CdA.

Agreed. (Just re-read the second line in your post, and that is a factor I had tried to account for my using all DSG vehicles in my calculations, but it's a good point. Might explain the difference between the 150PS TDI & TSI numbers, though the weight is also likely a factor.) 👍

 

Also, even around these very close numbers, either side of 150MPH, replacing the 220PS with the 230PS figures changes the calculated top speed result for a 210PS car.

Though there may be changes between the 220PS and 230PS vehicles which change the aerodynamics or weight of the vehicle slightly, changing the final top speed.

Different tyres between the vehicles would also be a factor in the top speed. (If they were different.)

And as @Roottoot just posted in his linked video, even different runs will yield different results.

I'm just trying to extrapolate from the manufacturers figures for fun.

Edited 25 July, 20205 yr by EnterName

Should have mentioned the stage 1 diesel Mk3 was an SE which I kept with the standard 16" alloys running 205/55 tyres for less drag. A friend had a Mk1 Civic Type R which revved to over 8,000rpm and between 30-70mph the Octavia matched it which is impressive given the Honda weighed about 1,100kg and had circa 197bhp.

The figures are kidology as the Co2 g/km, WLTP / RDE & RDE2 are.

VW, Audi & SEAT were caught cheating Co2 g/km after the Emissions Scandal, and still they do 'engineering of numbers'. 

 

For decades a Skoda with the same power / drivetrain as an Audi or VW will show poorer performance than a more expensive vehicle from the sister brands, 

even if they are actually heavier.

 

Then who really cares about Manufacturers figures with some 60kg driver that you do not know which Rolling Road they were on in a wind tunnel or not.

Or where ever above or below sea level in what ever ambient temp with tyres at whatever pressure and a near empty tank of fuel.

Stick a 100kg weight in each seat with a seat belt and 200 kg weight in the boot and see what the performance is when the cars are being used as many might be which is as Airport Transport / Taxis or Family vehicles.

3 minutes ago, Roottoot said:

The figures are kidology as the Co2 g/km, WLTP / RDE & RDE2 are.

VW, Audi & SEAT were caught cheating Co2 g/km after the Emissions Scandal, and still they do 'engineering of numbers'. 

 

For decades a Skoda with the same power / drivetrain as an Audi or VW will show poorer performance than a more expensive vehicle from the sister brands, 

even if they are actually heavier.

 

Then who really cares about Manufacturers figures with some 60kg driver that you do not know which Rolling Road they were on in a wind tunnel or not.

Or where ever above or below sea level in what ever ambient temp with tyres at whatever pressure and a near empty tank of fuel.

Stick a 100kg weight in each seat with a seat belt and 200 kg weight in the boot and see what the performance is when the cars are being used as many might be which is as Airport Transport / Taxis or Family vehicles.

Oh yeah, it's completely pointless and no doubt however carefully I do my calculations, like a school experiment, reality will intrude and the actual result will be different to the calculated result. 

 

5 hours ago, EnterName said:

Why 155 and not 150 though? Is it as simple as 250km/h is a nice round number?

250km/h = 155.343mph

 

Most manufacturers aren't "too careful" about how exact the speed limiter setting is, as an example my previous Audi RS4 was supposedly limited to 155mph but many owners (on level stretches of unrestricted autobahns) saw GPS speeds of 168mph (speedo indicated 180mph).

Edited 25 July, 20205 yr by PetrolDave