Dyno Results 09 JCW
#101
#102
:-) and from yesterday I also fitted a Milltek Downpipe , and I guess that it added some power too! I don´t know how much but 5-10 Hp?
#103
Those figures sounds about right, as with my 2011 has a but feel of about that. I know that there are those out there that are constantly down grading the JCW, but have never driven one for over a short test drive, if that. What amazed me, and still does, is the power from 10 mph up to 50 in 2nd and 3rd gear. And, I'm not talking about getting all the way in it, or in Sport mode. I'm impressed and very happy that I did bite the bullet and go with the JCW. Many say, under powered and over rated. I say they just got that backwards.
#104
**
A SemiImbecille understands what I'm talking about.
Last edited by MotorMouth; 11-18-2010 at 10:22 AM.
#106
#107
no not 228,5 at the wheels with standard engine , in some way it must be calculated from the wheels.. I only know that the company that done the dyno operates the most advanced dyno in sweden..
#108
#109
you aren't serious are you? The kind of dyno where you input the drivetrain loss and it calculates it for you (which i think all can). Almost every european dyno we see has done this especially if it says BHP. The problem is you have to guess what the drivetrain loss is. I've seen people on mini2 claim it is as high as 20%. Others say as low as 10%. OF course it isn't accurate but it can give a great "feel good" number.
#110
you aren't serious are you? The kind of dyno where you input the drivetrain loss and it calculates it for you (which i think all can). Almost every european dyno we see has done this especially if it says BHP. The problem is you have to guess what the drivetrain loss is. I've seen people on mini2 claim it is as high as 20%. Others say as low as 10%. OF course it isn't accurate but it can give a great "feel good" number.
That was my point... the rwhp (okay, fwhp) is only a "guess" or calculation at the loss. Since there is no way to measure drivetrain loss, then the only way to measure crank HP is with the engine out of the car.
....which is why I was saying I thought his numbers were at the wheels.
Sorry, I wasn't real clear on the way I was trying to make a point.
Mark
#111
That was my point... the rwhp (okay, fwhp) is only a "guess" or calculation at the loss. Since there is no way to measure drivetrain loss, then the only way to measure crank HP is with the engine out of the car.
....which is why I was saying I thought his numbers were at the wheels.
Sorry, I wasn't real clear on the way I was trying to make a point.
Mark
....which is why I was saying I thought his numbers were at the wheels.
Sorry, I wasn't real clear on the way I was trying to make a point.
Mark
ok, just keep in mind that many europeans are posting "corrected" dynos. BHP is a dead give away.
#112
looking at the dyno sheet - there is a thrid line called HP loss. I'm curious what that represents. Perhaps it's the correction factor. It looks like you may be able to subtract that line from the HP line to get HP atw. quick math would indicate they used ~18% loss
#113
#114
In dynospeak, Brake Horsepower is the appropriate term. A dynomometer, in its simplest form, is a brake. Check here: http://en.wikipedia.org/wiki/De_Prony_brake
you don't hear americans saying bhp on this forum. you do hear europeans saying it though - and it seems to always be "corrected" power.
edit: I just read your link and guess what? BHP refers to power literally measured at the output shaft of the engine. So when people say BHP they are incorrect unless the engine was not installed in a vehicle. Of course they can "guess" what the BHP is by using a guesstimate of the correction factor which is what I've been saying the whole time.
I stand by my earlier post:
Last edited by MotorMouth; 11-20-2010 at 08:46 AM.
#115
Any power source can work against a Brake (or a power absorption device). I think the term is much more general that you suggest.Conceptually, all a Brake does is absorb energy. The Brakes on your car absorbs the Energy of Motion, Kinetic Energy, in order to stop the car.
Last edited by flatlander_48; 11-21-2010 at 01:11 AM.
#116
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BHP vs. WHP
These terms are simultaneously confusing and misleading at times.
The term Brake Horsepower was first used in 1822 by Plobert and Faraday. As mentioned above, the "brake" refers to a hydraulic or electric brake at the crank. BHP represents measured (engine dyno) or corrected (chassis dyno) engine power before drivetrain losses.
The term WHP came into use after Carl Schenk created of the first chassis dyno with a brake in 1928. Wheel Horsepower refers to actual power at the wheels after drivetrain losses. It represents the total available power from the engine and drivetrain to the wheels. (Measured on a chassis dyno). Even though a hydraulic or electric brake is built into a chassis dyno, BHP is never used interchangeably with WHP.
The need for differentiation of BHP vs WHP comes up pretty frequently when folks are trying to make sense of dyno charts and we're not the first MINI forum or thread to discuss this. Here's the euro perspective on the same topic:
http://www.mini2.com/forum/first-gen...orsepower.html
As mentioned previously, manufacturers and bench racers love BHP because it's a bigger number than WHP. However tuners, racers, and trackday enthusiasts are more concerned with WHP because they actually want to know how much power is getting to the pavement.
So does anyone have any more dyno sheets to post and discuss?
-Clint
The term Brake Horsepower was first used in 1822 by Plobert and Faraday. As mentioned above, the "brake" refers to a hydraulic or electric brake at the crank. BHP represents measured (engine dyno) or corrected (chassis dyno) engine power before drivetrain losses.
The term WHP came into use after Carl Schenk created of the first chassis dyno with a brake in 1928. Wheel Horsepower refers to actual power at the wheels after drivetrain losses. It represents the total available power from the engine and drivetrain to the wheels. (Measured on a chassis dyno). Even though a hydraulic or electric brake is built into a chassis dyno, BHP is never used interchangeably with WHP.
The need for differentiation of BHP vs WHP comes up pretty frequently when folks are trying to make sense of dyno charts and we're not the first MINI forum or thread to discuss this. Here's the euro perspective on the same topic:
http://www.mini2.com/forum/first-gen...orsepower.html
As mentioned previously, manufacturers and bench racers love BHP because it's a bigger number than WHP. However tuners, racers, and trackday enthusiasts are more concerned with WHP because they actually want to know how much power is getting to the pavement.
So does anyone have any more dyno sheets to post and discuss?
-Clint
#117
But with HP at crank what should it have been if uses SemiInbecilles 12 % Loss instead ?? My maths is not so good..
#118
talked to JRM which has the dyno machine , they says that the dyno itselfs calculates the braking and the loss with detecting the enginebraking from letting the pedal up at max rpm on 4th gear and then down to 0 again..
#119
I don't know for sure that the third line is indicating how much loss there is. IF it is that would indicate roughly 190whp which is a little lower than several JCWs have posted. Even at 190whp though you'd still be hitting the advertised 208 at the flywheel using a 12% correction. With the dyno shop saying they measured the loss 228bhp could be right.
However 228whp on a barely modified untuned r56 is unheard of. 228bhp would not be unusual.
Get a tune and you'll be grinning hugely no matter what the dyno says.
#120
#121
It looks like that dyno is similar to a Maha dyno, which are very popular in Europe and used by most of the OEMs.
They are highly accurate, and they can plot drivetrain loss for every run across the entire rev range. Drivetrain loss is not a static number....it varies between each car, and also increases through the rev range. When the run is completed...they release the throttle and let the engine/wheels slow down on its own, and it is during this time that the dyno can sense the effort it takes to slow the wheels down, and plots drivetrain loss.
There is a local shop here in Scottsdale that has one...I have never had my car on it, but have seen friends cars on it and it is quite the machine. They are very expensive.
Still not as accurate as an actual engine dyno....but they are darn close.
They are highly accurate, and they can plot drivetrain loss for every run across the entire rev range. Drivetrain loss is not a static number....it varies between each car, and also increases through the rev range. When the run is completed...they release the throttle and let the engine/wheels slow down on its own, and it is during this time that the dyno can sense the effort it takes to slow the wheels down, and plots drivetrain loss.
There is a local shop here in Scottsdale that has one...I have never had my car on it, but have seen friends cars on it and it is quite the machine. They are very expensive.
Still not as accurate as an actual engine dyno....but they are darn close.
#122
It looks like that dyno is similar to a Maha dyno, which are very popular in Europe and used by most of the OEMs.
They are highly accurate, and they can plot drivetrain loss for every run across the entire rev range. Drivetrain loss is not a static number....it varies between each car, and also increases through the rev range. When the run is completed...they release the throttle and let the engine/wheels slow down on its own, and it is during this time that the dyno can sense the effort it takes to slow the wheels down, and plots drivetrain loss.
There is a local shop here in Scottsdale that has one...I have never had my car on it, but have seen friends cars on it and it is quite the machine. They are very expensive.
Still not as accurate as an actual engine dyno....but they are darn close.
They are highly accurate, and they can plot drivetrain loss for every run across the entire rev range. Drivetrain loss is not a static number....it varies between each car, and also increases through the rev range. When the run is completed...they release the throttle and let the engine/wheels slow down on its own, and it is during this time that the dyno can sense the effort it takes to slow the wheels down, and plots drivetrain loss.
There is a local shop here in Scottsdale that has one...I have never had my car on it, but have seen friends cars on it and it is quite the machine. They are very expensive.
Still not as accurate as an actual engine dyno....but they are darn close.
#124
OVERDRIVE
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Fascinating!
We have just used technology to 50 years backwards. Back in the ’60 there were all sorts of articles to do just this sort of thing to determine horse power and drive train losses. You would clock the car from 10 to 20mph, 20 to 30, 30 to 40 etc. Then you would do timed coastdown to get drive train and areo losses. From the equation F=ma you can calculate Hp from acceleration or deaceleration times and weight. Add the 2 together and you have the engine HP. There you have it HP without a dyno.
Now it is interesting that car mags like Road and Track state the 2007 MCS will do 0- 60 in about 6.4 sec. For the Mini’s weight including driver that works out to about 194 HP. Also, if you look in the owner’s manual the torque in over-boost mode is 192 ft-lb from 1700 to 4500 rpm. Calculating HP from torque and rpm, the peak in that range is 195 HP. Now before everyone jumps on me…the over-boast is only for about 10 sec and then you are back to the 172 Hp rating, so the 194 Hp will not show in a dyno. It is also the reason the 0-60 times for a JCW are not leaps and bounds better. The real value in the JCW is the sustained 208 HP which is available at any time…There have been many times that I have felt the acceleration disappear when the over boast disappears.
The other interesting thing is that the Mini factory rating is at the crank shaft and I have seen a lot of dyno posts where the WHP is pretty close to the factory rating. To me, given the typical drive train losses, that says that Mini has underrate the engine. Go Mini
We have just used technology to 50 years backwards. Back in the ’60 there were all sorts of articles to do just this sort of thing to determine horse power and drive train losses. You would clock the car from 10 to 20mph, 20 to 30, 30 to 40 etc. Then you would do timed coastdown to get drive train and areo losses. From the equation F=ma you can calculate Hp from acceleration or deaceleration times and weight. Add the 2 together and you have the engine HP. There you have it HP without a dyno.
Now it is interesting that car mags like Road and Track state the 2007 MCS will do 0- 60 in about 6.4 sec. For the Mini’s weight including driver that works out to about 194 HP. Also, if you look in the owner’s manual the torque in over-boost mode is 192 ft-lb from 1700 to 4500 rpm. Calculating HP from torque and rpm, the peak in that range is 195 HP. Now before everyone jumps on me…the over-boast is only for about 10 sec and then you are back to the 172 Hp rating, so the 194 Hp will not show in a dyno. It is also the reason the 0-60 times for a JCW are not leaps and bounds better. The real value in the JCW is the sustained 208 HP which is available at any time…There have been many times that I have felt the acceleration disappear when the over boast disappears.
The other interesting thing is that the Mini factory rating is at the crank shaft and I have seen a lot of dyno posts where the WHP is pretty close to the factory rating. To me, given the typical drive train losses, that says that Mini has underrate the engine. Go Mini
#125
Power ratings!
Fascinating!
We have just used technology to 50 years backwards. Back in the ’60 there were all sorts of articles to do just this sort of thing to determine horse power and drive train losses. You would clock the car from 10 to 20mph, 20 to 30, 30 to 40 etc. Then you would do timed coastdown to get drive train and areo losses. From the equation F=ma you can calculate Hp from acceleration or deaceleration times and weight. Add the 2 together and you have the engine HP. There you have it HP without a dyno.
Now it is interesting that car mags like Road and Track state the 2007 MCS will do 0- 60 in about 6.4 sec. For the Mini’s weight including driver that works out to about 194 HP. Also, if you look in the owner’s manual the torque in over-boost mode is 192 ft-lb from 1700 to 4500 rpm. Calculating HP from torque and rpm, the peak in that range is 195 HP. Now before everyone jumps on me…the over-boast is only for about 10 sec and then you are back to the 172 Hp rating, so the 194 Hp will not show in a dyno. It is also the reason the 0-60 times for a JCW are not leaps and bounds better. The real value in the JCW is the sustained 208 HP which is available at any time…There have been many times that I have felt the acceleration disappear when the over boast disappears.
The other interesting thing is that the Mini factory rating is at the crank shaft and I have seen a lot of dyno posts where the WHP is pretty close to the factory rating. To me, given the typical drive train losses, that says that Mini has underrate the engine. Go Mini
We have just used technology to 50 years backwards. Back in the ’60 there were all sorts of articles to do just this sort of thing to determine horse power and drive train losses. You would clock the car from 10 to 20mph, 20 to 30, 30 to 40 etc. Then you would do timed coastdown to get drive train and areo losses. From the equation F=ma you can calculate Hp from acceleration or deaceleration times and weight. Add the 2 together and you have the engine HP. There you have it HP without a dyno.
Now it is interesting that car mags like Road and Track state the 2007 MCS will do 0- 60 in about 6.4 sec. For the Mini’s weight including driver that works out to about 194 HP. Also, if you look in the owner’s manual the torque in over-boost mode is 192 ft-lb from 1700 to 4500 rpm. Calculating HP from torque and rpm, the peak in that range is 195 HP. Now before everyone jumps on me…the over-boast is only for about 10 sec and then you are back to the 172 Hp rating, so the 194 Hp will not show in a dyno. It is also the reason the 0-60 times for a JCW are not leaps and bounds better. The real value in the JCW is the sustained 208 HP which is available at any time…There have been many times that I have felt the acceleration disappear when the over boast disappears.
The other interesting thing is that the Mini factory rating is at the crank shaft and I have seen a lot of dyno posts where the WHP is pretty close to the factory rating. To me, given the typical drive train losses, that says that Mini has underrate the engine. Go Mini
Back to Mini's: I, personally think that either, Mini/BMW under rates the engines, or only rates them at lower rpm. Just about all the MCS that get dynoed have whp very close to the supposed advertised hp at the flywheel.
As for the JCW, well Lil Guy and I are still in our love affair period, but this is what I have found so far. At the speed where most cars that I have ever owned before fall off, Lil Guy pulls, and hard. Like in the 65-80 speed range. That's in 6th gear, no dropping down a gear. I, just haven't found a speed range where it falls off, unless you want to say in 6th gear at 40 mph. The one MCS that I test drove in January, it felt good, but in the 30 to 60 range, it felt sluggish. I tried this with my JCW and it pulled. That was in 4th gear. But, other than the odd speeds, there isn't a lot of power difference, as in the advertised power ratings between the two. The JCW just has more power thru the entire power range. Now there will be those that say, well just add a cai, bigger tubes, Helix i/c bigger exhaust and such and I can beat all the JCW's. What I'm referring to is a stock JCW and a stock MCS. They're both excellent, it's just that the JCW pulls a bit more thru the range.
Had to comment on this, as Lil Guy are still new to each other and I thought that I'd post what I am finding.