So one day a few months back, I was trying to compare real-world horsepower numbers on the various models of MINI, and I couldn't find anyone who has dyno'ed all the cars on the same dyno. I mention this to the local MINI crowd, and we got to talking, and someone (okay, it was Edge) said, "Hey, YOU have a dyno..." and that's how the idea of a one-day stock MINI dyno test was hatched.

The idea: Dyno as many stock MINI models as possible on the same dyno, on the same day.

I wanted to try to keep things as simple as possible, so I suggested we stick with the 2002-06 cars. (We do happen to have an '07 MCS shop car...more on that later.) Furthermore, I wanted all manual-trans cars, to reduce complications caused by trying to dyno automatic cars. Our candidates needed to be completely stock, no power mods of any kind.

Our gracious web host Mark (founder of this very web site) agreed to help offset the cost of the dyno day. Mach V Motorsports (that's my company) paid for the rest. The participants (lucky them!) got free dyno numbers.

We put the call out for stock cars of various types, and we got the following:

- R50 Cooper
- R53 Cooper S (two, actually)
- R53 Cooper S JCW package
- R53 GP
- R56 MCS (our shop car)



Our dyno is a Dynojet model. Conditions in the shop were around 45% humidity and in the mid-80's. All dyno runs were done in fifth gear on the six-speed cars, fourth gear on the five-speed MC.

Here's what it looks like:



We did collect air/fuel data using a tailpipe wideband probe. We warmed up each car, and made three passes, with cool-down time between. The numbers I'm showing here are the highest of the three passes for each car.

Here are the numbers for the R50/R53 cars. The figures are horsepower AT THE WHEELS. I use a rule of thumb of about 15% drivetrain loss from crank to wheel numbers, but that's just a general rule. Based on stock horsepower ratings, these numbers came in pretty darned close to that. (By that I mean, a stock JCW is supposed to have 207 hp at the crank. Figuring 15% loss, I'd expect around 176 at the wheels. We dyno'ed today at 173.)

Smoothing reduces jaggies in the graphs. If you turned smoothing to "0" you'd get about a 1 hp increase in the max power of each car. SAE correction (which adjusts for weather conditions) is on, but I think in almost every case SAE correction was 1.00, meaning the numbers are the same as uncorrected.



The lines above are (from lowest to highest) R50, R53, R53 JCW, and R53 GP.

One comparison I found interesting was the stock R53 Cooper S with the JCW version:



Notice how the torque difference increases with RPM -- that leads me to believe the major source of difference in the two is the higher-speed supercharger, which gets faster with RPM. (I know, this isn't exactly news, but it's interesting to see it in the dyno numbers.)

Someone at the dyno event said he believed the fuel tuning of the supercharged models left a lot on the table. And to be sure, if you look at the GP model (which boasted the highest horsepower), it did run a little leaner than the JCW, which was just a tiny bit leaner than the standard Cooper S. But all of them look pretty good -- nice and lean (lean mixture makes good power!) at low RPM, and gradually tapering down to 10.0:1 near readline, where the danger of detonation is higher. No unseemly bumps or glitches.



Here's another interesting tid-bit: We actually had TWO stock '05 Cooper S models. I sort of lost track of who I said should come, and they both showed up, so we dynoed both. The result:



Whoa! They're within 1 hp and the torque number is virtually the same! I think that's comforting for a couple of reasons. First, it's reassuring that dyno is consistent, although we pretty much know that from experience. Second, it's kind of cool to see that two of the same model do perform the same.

All the supercharged models had that odd dip around the 3000 rpm range. NAMer JustJAY suggested that it's fixed by changing out the bypass valve. Perhaps we'll be able to verify that with a future dyno test.

As I mentioned, we did have our stock-power '07 R56 MCS on hand, so we also dyno'ed that:



(That's plotted against the GP for comparison.) The R56 is the red plot. For whatever reason, our car was down about 6 hp and 2 ft-lbs compared to the last time we ran it, but the difference is still pretty dramatic. It's awesome to me that you can get this much torque in even the most basic Cooper S these days. $22,500 and 200 ft-lbs to the WHEELS!

We plan a future test of stock R56 models, including factory JCW packages as well as the newer R56 MC. That should happen sometime next year.

I'd like to thank NAMers Mark, Edge, MiniNURSE, and Sam for their help in getting this event together; to reechard, tnkgurl and her husband, Chili Pepper, Scrumpy_Jack, and minifiddler for allowing us to dyno their cars; to my faithful staff-members Will and Evan, who worked and sweated all day; and all the other MINI fans who showed up today. I had a great time, and learned a lot! Getting out of the parking lot was a pain, though, owing the the traffic jam:





--Dan
Mach V Motorsports
FastMINI.net

 

Just as I predicted... the GP did indeed demonstrate a higher peak HP value than the R56... even though the peak torque values were way, way in the other direction. Also, at very high RPM (5800+), the GP has more torque too, which does indeed confirm my belief that the Tritec engine continues to pull hard at the top end, whereas the Prince engine drops off a LOT up there. I noticed that when I test drove the R56.

As a "general" statement then, I'd venture to say that the stock Prince engine has more "usable" power for day-to-day driving, which suits most people better... but for those who love to "wind it up", the feeling of a continuous pull, all the way to the redline, plus the aesthetic sound of the screaming supercharger, the Tritec experience is unmatched.

Two completely different engines, with very different experiences. Overall, sure... the Prince is going to be faster... but there are still some valid reasons why some of us 1st Gen folks are gaga over the Tritec "experience".

A very, very worthwhile exercise... same day, same dyno, fair and equal comparisons of all of the stock models... awesome!

 

It was a great day! Just to be able to see all these done with the SAME conditions it was really cool to see how they all came out! Great job Dan. I am so happy that you had this event!

 

+1 Dan I had a nice time as well. If you want to do another dyno on a R53 MCS with a modded BPV before April 08, let me know, I have a modded BPV sitting in my closet Good job on the dyno and can't wait to get some gauges installed.

 

So from the Dyno numbers, the R56 does not lose any horsepower or torque from the crank to the wheels?

Also, I'm assuming Dan had the Sport button on when doing his Dyno runs.

I had a good time as well. Thanks Dan. I was a pleasure doing business with you as well

 

Huh? Where did you get that from?

 

R56 rated 175 hp at the crank (factory number), yesterday dyno 170.98 @ at the wheel.

That's why I couldn't cut lose r30e56 from tailgating me yesterday, very impressive indeed.

 

Ah, ok.

 

Oh wow, that's why there was so many MINIs yesterday. I was the guy with the DS JCW R53! I had a trunk full of wheels, heh.

 

You all should have hung out and said hi!

 

You should look/post in the DCMM forum if you want to do something with other MINIs.

 

It probably loses just as much as the others. It just has more horsepower than its advertised number. 171/0.85 = 201-ish at the crank.

No. But the Sport button only changes steering feel and throttle curve; it doesn't change power.

Thanks!

--Dan
Mach V
FastMINI.net

 

It would be funny to plot the R56 on the same plot as a honda K20 with the Vtec coming in at 5k. The engines are exactly opposite. Coming from a K20 the R56 sure is more convient to drive around and way better for autocross where i dont want to be shifting, but there is a fun element of blasting up to the top end that you just dont feel on the R56. I sure miss that . But then I go up a hill in 6th gear, I sure like that .

 

Hi....., we saw you in front of the CWF when we stop by for lunch.

Awesome plate though, DC MINI

We waved, ..... about 10 times.

+1, , only that I'm from the legendary B18C5.

 

Yeah, that's why I was so confused. Factory specs say 172 HP and 177 lb-ft Torque. The R56 put down 171 HP and 200 lb-ft Torque AT THE WHEELS . That is a HUGE difference. So really the R56 specs should say 201 HP and 200 lb-ft Torque?

 

Half-right! Since the torque is also scaled down at the wheels, torque at the crank is more like 201/0.85 = 236 ft-lbs!

--Dan
Mach V
FastMINI.net

 

WOW! That is a really big difference then. Thanks for clearing that up Dan. I learn something new every day

 

Grassroots Motorsports Magazine had similar results when they Dyno'd an r56. Virtually no change from crank to wheel. Mini may have understated the HP/ Torque numbers to fool the Insurance companies. I here HP is a big factor in car insurance in Europe.

 

Yeah, that's what my friend was saying. It's the insurance factor.

 

This is definately a nice comparo. It's nice to see the stock number put up next to each other like that. the numbers on the r56 are very impressive. I can see how the numbers are understated. BMW seems to do that with a lot of cars (probably for insurance purposes as previously stated).

 

They are also notorious about lying about the weight of the car. Increasing the mfr spec'd weight so the power to weight ratio doesn't look as high!



I also find it strange that the GP made that much more power than the std. JCW. Is the difference just from the intercooler????

 

The GP has a higher redline and a different ECU program, in addition to the larger intercooler. Notice that it had a leaner air/fuel curve at higher RPM.

--Dan
Mach V
FastMINI.net

 

Sure. But I wasn't really referring to that as much as the gap across the entire TQ and HP curve. If you stop at where the std. JCW power drops, its still making a good bit more power. Also the difference in the A/F doesn't equate to a visable difference in the graphs. I think something else is going on here.

Perhaps it's just the timing from the tune? The A/F ratios are similar until about 5k, then the GP's leaner, but that's not where it's gaining, it's gaining everywhere! So... again, could this just be a combo of the intercooler and the timing from the tune?

 

Yes, probably. The larger intercooler may allow for more advanced timing.

--Dan
Mach V
FastMINI.net

 

that must mean it's got more cooling capacity and no pressure drop