I finally had some time to collect together some initial data and analysis from the latest round of modifications to my heavily modified 2004 MCS. Over the last couple of years I've steadily progressed through multiple stages of enhancements/improvements. One of the motivations for this has been my steadily increasing interest in DE track events. Fortunately, I have had an *excellent* shop nearby (BHS) to make it all work together efficiently and reliably at each stage. Thanks BHS!!

To cap it off, I recently had the opportunity to buy the components for a twin-charge (Supercharger+Turbo) kit at a very good price. With a good bit of rework, BHS was able to produce a well-integrated system with a very non-turboesque behavior (as you will see below). Here is a picture of the installation, including my crude but effective temporary heat shield:




So without further ado....

NOTE: if you think that Dyno runs do not accurately reflect real-world performance, you can skip to the Track Results section...but no peeking at the graphs :-).


Dyno Results
------------------

I have been pretty consistent with getting a dyno run on the same machine after each modification, so I have a pretty good history of the performance gains at each stage. The following graph shows the progression through various stages of upgrades over the last couple of years, starting with the initial (lowest) graph shows my car when it was a relatively stock JCW (It did have the GRS intercooler though). As you can see, the initial run showed fairly normal JCW numbers, i.e. 170whp and 150ft lb torque:



To make a long story short, with the addition of the turbo, it's progressed to a *much* higher level:



The really phenomenal thing about this is the tabletop-flat torque curve through most of the power band, and the consistency from run-to-run. It behaves & sounds much more like a bigger engine than a turbo.

Moreover, I do not get the sense that we are pushing the system anywhere near it's limits...which is good!


Track Results
------------------

I had the chance to try the car out on the track for the first time at the Texas BMWCCA DE event a few weeks ago. The event was held at the MSRC track near Dallas. It's a technical track with medium length straights that favors cornering over power, so I wasn't expecting it to be magically different than before.

Net net, the car was *fantastic*. Even though it was the first outing & I wasn't pushing the car to the limit, I improved upon my best lap time for that track by over two seconds.

And it really felt like a very different car....which also means that I have to totally relearn how to drive it. There were at least two turns that I used to be on full-throttle at the apex that I couldn't anymore because I was spinning *both* of the front wheels - even with a quaife differential and wide sticky tires!

It was also amazing how consistent the car felt throughout the day. I did not sense any loss of power or heat soak. And I was especially amazed at how relatively cool the Intercooler stayed. Granted, each run ended with a cool-down lap. But I opened the hood as soon as I got back to the paddock, and I could immediately put my hand on the intercooler (warm but not hot).

To get a feeling for it yourself, here's a video from the afternoon session. As a point of comparison, before this upgrade I (car+driver) was pretty equal to the green Mini (car+driver) I pass mid-way through the video. And the Miata in the video is a heavily modified with a Turbo...they don't usually take me that long to pass :-)

Note: the audio is a bit deceptive. With the waste gate open, the car is *very* loud now. So I had to really turn down the Mic input...which means you don't hear much of the normal engine sound until the Turbo is fully spooled up:




Finally, I have a data logger hooked up to gather standard GPS information as well as RPMS, Oil pressure/temp, boost, A/F Ratio, etc. I'm still analyzing the data, but so far it looks good. Just to give you a sample, here is a graph of the boost vs. speed for one lap:



Here's a rather complicated graph indicating boost, A/F Ratio and RPMs for one lap:



I'm also experimenting with a math channel that calculates deviation from "theoretical optimum power delivery". With a perfect car & driver this graph should be zero everywhere. Overlaying this run with one from last year, you can see how the peaks are generally sharper indicating faster acceleration/deceleration. But in other areas it's actually worse...mainly because I'm wasting too much time spinning the wheels and/or being less consistent through the turns...more confirmation that the biggest thing needing improvement now is the nut behind the wheel :-) :





I can't wait for the next event... Thanks again to BHS for all the hard work!

 

Those look like great numbers.

Glad to see someone else is out there experimenting with radical performance mods.

Looks like the twin turbo system reduces spool times quite a bit. Similar setups with a single turbo are spooling close to 4k RPM's. Seems like yours spools right before 2800, which represents an average factory turbo car.

Look forward to more info!

 

Looks good and the video is awesome but it sounds like you are a slow shifter

 

Coming to this weekends 3 day PCA event at ECR??

 

Granted I could *definitely* be better...but the sound is a bit deceptive. There is almost a full second delay between when I shift & when the waste gate opens (which is what you're hearing).

 

I want to, but taking off for three days is a bit tough right now. Do you think they would let me just do two out of the three days??

 

Look at the AFRs around 3.5k . It looks to me like stoichiometric??? You're running wayyyyy lean. What kind of tuning do you have? What injectors? I hope you're not running too much timing... What peak boost are you running? More info. please (slightly scared for you )?

Anyways, how is the part-throttle driveability? Jan's stroker makes around that much torque but a little less peak power (with just the stock M45 S/C). It has the huge benefit of stock driveability and reliability. The only twincharged car that I've been in had uneven power delivery with tons of flat spots, which would kill me around town. From what I understand all twincharged setups have this issue because the ECU can't handle the different boost curve of the turbo.

Bottom line, sweet that you're now twin-twincharged and those are some sweet numbers. Looks like a great track machine. Get it tuned so you can continue to enjoy it!

PS: Love the electric blue (you have impeccable taste)

 

What other mods do you have on your car? a head? what cam? And, how did you toast the piston that you have in your gallery? Ouch... Watch your AFRs or you may have the same happen again .

 

Pretty yummy stuff.

 

I should have said that the A/F curve from the dyno is about 1 pt richer across the board than it appears. The logged on-board A/F sensor confirms this. And just to be sure, after the first day on the track I pulled the spark plugs to check how they were doing & they were actually running a bit too *rich*. Moreover, the pistons have been replaced (the classic weak point).

The injectors are 440 R/C injectors which are matched to each other.

On the street I'm currently running 20psi boost. I do have a 22psi setting for the track, but I wasn't using it in that video. and I'm sure it can go much higher than that.

As far as driveability, there are no flat spots or discontinuities in power delivery at all. It just simply feels like it is a bigger engine... And I have no problem driving part throttle every day in stop-and-go traffic.

 

Its a great price even if you do only 2 days, which PCA essentially said in an earlier EMail. You probably do have to be there Saturday morning for registration. According to the tentative schedule Monday has 3 sessions instead of 4.

C'mon man, you'll be the 4th MINI. 2000 foot straight - I'll hate you by the end of the weekend.

Alan

 

I'm sure if you didn't show for a day it would not be an issue. I'd imagine Monday a few folks won't show up. Tomorrow is the last day to register.

 

That piston was what started my bigger round of improvements almost two years ago. The current pistons are *much* stronger . And yes, I'm very aware of A/F ratios... but actually that failure was caused by a single faulty injector. That doesn't necessarily show up in the combined A/F ratio.

I'll post some more info on the other changes tonight when I have some time...

 

Very cool Nice vid.

 

wow, very nice!

 

Very impressive and thanks for the video, it gives us a good sense of the power delivery on the track.

How is power and traction from a dead stop?

Thanks again for posting the comprehensive results.

 

Thanks for sharing your track impressions Works4me!

That looks like a fun little track!

Jeremy

 

congrats on developing a nice track-worthy MINI. power levels are great and drivability is better. again, nice work.

 

I'm not sure if I missed it or I'm just not understanding, but just to clarify...this is a twin-turbo kit?? As in no supercharger, but 2-turbos? Or is it a turbo only kit.....or a twin-charged kit?

Nice numbers though! It was great being able to see the video too, the power delivery seems great.

 

Sorry, I wasn't very clear on that. Supercharger + Turbo.

At the track other people started calling it a "Super-Turbo"... I kinda like that

 

ahhhhh, i see! I got all pumped thinking that someone had created a twin-turbo MCS.

Still really cool, I've always thought twincharging was cool too!

 

Good driving. Impressive.

 

So there's one turbo and one supercharger??

 

err....yes.... The supercharger is the standard unit (more-or-less). The turbo was added to the intake+exhaust to provide additional boost. Thus the term "twincharged".

FYI, There are a number of twincharged Minis around nowadays....

 

Nice numbers and great vid . Looks like you are having fun.

Longboard