RR Day 7 - At last, He booked it !
- Thread starter Conanius
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Am I right in thinking you work at powerstation or am I getting confused with someone else.
Soldato
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Yeah that's Andy, aka Fuzz from PS.
Ah ok, I wonder if he could wxplain to me (as I am getting a lot of moaners on the owners club) why the wheel figure is wrong?
They are a bunch of asses.
Soldato
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I know what you mean about moaners on the forum, I got it here when I took my old Impreza Sport to Powerstation, yet nobody believed me until they all went and got rubbish wheel figures 
Hi there
Are you saying the CSL felt very raw in comparison to the M5, sorry hard to work out and as such you think a standard M3 may feel a bit more like an M5?
M5's are heavier, built more for cruising but still with the ability to be very quick in the twisties. A standard M3 will still be more hardcore over an M5, its just the CSL takes it to the extreme, even though its still a perfectly fine car for daily use.
The @ the wheels figure is an IN DYNO at the wheel figure not a road wheel figure.
The wheel (tyre actually if you want to be pedantic) is not only being pinched in between two rollers, you are also doubling it's normal contact patch which again increases drag.
All I can say is, using the thing day in, day out, lots of standard cars make standard figures.
However there are a noticeable few models which also make consistent high and conversely low figures.
Get a group of those cars together and suddenly the dyno is reading high (or low) when in actual fact manufacturers (I guess) have fudged the figures to fit their own agendas....
Ones of the top of my head for eg.. Focus RS generally reads high, whereas Pug 205 GTI 's read low..
The wheel (tyre actually if you want to be pedantic) is not only being pinched in between two rollers, you are also doubling it's normal contact patch which again increases drag.
All I can say is, using the thing day in, day out, lots of standard cars make standard figures.
However there are a noticeable few models which also make consistent high and conversely low figures.
Get a group of those cars together and suddenly the dyno is reading high (or low) when in actual fact manufacturers (I guess) have fudged the figures to fit their own agendas....
Ones of the top of my head for eg.. Focus RS generally reads high, whereas Pug 205 GTI 's read low..
Soldato
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Thanks for that Andy, makes quite a bit of sense.
Cheers so is there any way to calculate the wheel figure then from the graphs or is it impossible?
I wouldn't know how to work it out if it can...
There is technical documentation on Maha.de if you wish to scratch your head over it.
http://www.maha.de/datenbank/support/ba/books/gb/0523B04G.pdf
Starts page 21
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Good explanation, and certainly explains why the ATW figures are generally low when using these rollers, now everyone knows why
That makes sense.
Were getting loads of grief on S2ki forums (Me and Cocopops) about our wheels figures
Regardless though, it made 245 DIN stock, then 249 DIN earlier this year and yesterday 255DIN (260hp measured though )
ther
Interestingly I ran my old Rover Turbo at PS and it made 199.9 @ wheels there, another place a few weeks later and it made 234 @ wheels. Both runs were 260hp at the fly though
Were getting loads of grief on S2ki forums (Me and Cocopops) about our wheels figures
Regardless though, it made 245 DIN stock, then 249 DIN earlier this year and yesterday 255DIN (260hp measured though
)ther
Interestingly I ran my old Rover Turbo at PS and it made 199.9 @ wheels there, another place a few weeks later and it made 234 @ wheels. Both runs were 260hp at the fly though
Bhp = (rpm x torque)/5252
So if you take the maximum torque figure and the revs at which it occurs then you can work out the bhp figure
Which measurment of torque though?
There is only one measurement of torque and thats the one being read off the rollers by your wheels spinning it round
My plots above where it says est flywheel torque was written on by a numpty technician afterwards.
edit: oh and the equation above is for ftlbs else you are mixing imperial and metric terms
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Cheers that is what i was looking for, gives me a lower figure than the rollers, so dont want to say it.
Cheers that is what i was looking for, gives me a lower figure than the rollers, so dont want to say it.
What about 167bhp you mean
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What about 167bhp you mean
No 270 something lol
That's exactly my thoughts Gibbo.