That comes out to 228/224 in US standard measurements... which is pretty impressive for a stock vehicle.

Sounds like you don't need a tune...lol.


Mark

 

:-) 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?

 

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.

 

That comes out to under 200hp ATW if using 15%. He said CRANK power - and he's only pushing 14lbs of boost. I suspect 15% was not the % used.
how did you get crank figure? What drive train loss % did you use? What was your at the wheels number? We use ATW around here since no one really knows what the loss is.


**
A SemiImbecille understands what I'm talking about.

 

I dont nknow how the Dyno technically works , this was the sheet I recieved fromthe comapny taht did the dynotest..

 

I'm afraid according to that dyno graph, those numbers are at the wheels, are they not?

What kind of dyno can give crank numbers without the engine out of the car?

Mark

 

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..

 

this is the kind of dyno used http://www.vtech.se/tools/dynos.html

 

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

 

ok, just keep in mind that many europeans are posting "corrected" dynos. BHP is a dead give away.

 

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

 

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:

 

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.

 

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

 

so my WHP would be 201 then (at 18% loss ) .
But with HP at crank what should it have been if uses SemiInbecilles 12 % Loss instead ?? My maths is not so good..

 

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..

 

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.

 

Tune is on the way for me and Ola
I have a Alta Accessport and waiting for Jeff at Alta to finish a tune for Euro Spec JCWs
With a little luck maybe Jeff finishes it this week

(The choice of companys doing a good tune in Sweden isn´t so good)

 

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.

 

exactly the way they explained to me how it works..

 

Isnt 18% considered pretty high drivetrain loss for a FWD car? I always was told to expect closer to 10, and 15 for RWD and 20 for AWD.

 

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

 

Kind of woke me up to how we use to figure the power ratings in the mid to late 60's. My group use to use the 1/4 mile times. We didn't worry all that much about the horsepower, as the factories all played games with those, anyway. The magazine cars never were what the factories sold us. A friend of mine that was very close to those in the know at Chrysler told me that all the magazine cars with Chrysler used blueprinted engines. GM upped the cubic inches, as: 396 Chevells and Camaro's all had either 427's or later 454's. Ford either blueprinted theirs or in the GT 390's used 427's.

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.