Dyno day was fun. Saw some pretty cool cars (not just MINIs)... and some other cars that reinforced the addage "don't judge a book by it's cover". Specificlly a few ratty ricers putting up some scary figures (300hp out af a civic!?! A 450hp older rx7!?!).

Used a Dynojet and Winpep 7 program

Other stuff (some I didn't understand):
Gear - 3rd
Run Type - RO (?)
Temp - 53.45 degrees F
Humidity - 61% humidity
Uncorrected - 1.00 (?)
CF - Uncorrected (?)
Smoothing - 5 (?)

Max power = 180.21(hp) between 5600-5700 rpm
Max torque = 204.25(ft-lbs) @ 4400-4500 rpm

Power and torque curves were nice and smooth, confirming my seat-of-the-pants opinion of the R56S JCW (or at least MY R56S JCW).

Power was a little down from what I had hoped, as I've seen other R56s JCWs topping out between 187hp and 193hp at the wheels. The UK chart first posted was 206bhp!!! (I'm guessing that had to have been a corrected number estimating power "at the crank"... otherwise, we're really getting ripped in the US!!!).

I have no idea what factors could have come into effect causing me to be 7-10 hp off from other US hp numbers out there. Then again, the Hawaii car shown earlier was putting out 170hp... so, I don't know. It's all new to me. Maybe someone else can give me a little education and provide some insight.



If this one is too hard to read... the GREAT BIG version is in my gallery.

 

The UK figure of 206hp was corrected ( crank ) power. So 180whp is about right.

The power curve is so flat between 4-6k revs. That's the reason the R56 is so quick compared to R53JCW / GP in my opinion.

 

I also thought power runs were supposed to be carried out in 4th gear as a near to 1:1 ratio ?. Isn't 3rd gear likely to give a slightly higher figure ?.

 

it´s really interesting, another R56 jcw dyno results, thx so much

Most of the dynos in spain, gear used is 5th (in 6speed cars), 4rd in cases 5speed cars, i´ve never seen 3rd gear used at dynos for a 6speed car

curves and forms are right, more or less, really i was thinking peak power jcw r56 would be at 6k rpm, and the max power looks a bit low (so knowing is whp), sorry.

In three weeks i´m going to install jcw kit and i will return my car at the dyno to compare with stock results past june, i´ll post the results, both.

regards from spain

 

I think the dyno takes gearing into account by comparing engine rpm vs wheel rpm. the run just is over faster in a lower gear.

 

So if the average driveline loss is 12-14%, then...

180.21 x 1.12 = 201.83
180.21 x 1.13 = 203.63
180.21 x 1.14 = 205.43

OK. I can live with that.

 

Yup - I would be just fine with that figure too, especially since BMW-MINI are publishing 189 bhp as the official power rating. Awesome.

I have a question. Shouldn't the formula for calculating the crank hp rating be:
180.21 x (1.00 / .86) = 209.55 bhp for 14% drivetrain loss
therefore a 12% loss would yield about 204.78 bhp (?)

 

This really makes me wonder what kind of numbers the factory kit is going to put out if this is just a few hp down from the 210 or so that is currently being tossed around.

 

Probably . Someone just suggested elsewhere the average front wheel drive car had from 12-14% loss. I just assumed you could multiply it by 1.1X and get the additional percentage. I've never been the best mathmatician, though, so...

Yeah, I wasn't sure what to think, either. Should I feel slighted that it's not the 193hp at the wheels (the number that MINI suggests should come from the R56S JCW, but doesn't specify where it was measured)... or really pleased that its supposedly making much-much more than that at the crank? Just where, why and how is MINI getting their power figures?

 

I think that it is pretty standard for auto manufacturers to provide the crank hp rating as their spec. Also, I know that BMW is notorious for under-rating their motors.

Soooooo - I think you should be very pleased.

 

What does the JCW mod cost if you didn't purchase initially?

 

Same as if you ordered it straight-away = $2100 + 2-hours labor. Some have been sucessful working deals on parts and accessories, though. Never hurts to try.

 

All car companies use crank numbers.