While that's all fine and true, none of it is on point, and there no explaining away the fact that the experimental technique was less than ideal. That's not a flame, it's the truth. In the world of peer-reviewed scientific publications, this study would have been rejected because of parts of the technique that don't cover sufficient control. This isn't to say that the results are accurate, or they're not, but without baseline confirmation, they are indeterminant. While you can say you'll redo the work if I foot the bill is all fine and well, you're the team that chose the measurement regimin in the first place. I"m just a bit dissapointed that improper design of experiment takes what would have been an A+ effort into B class results. If the car had re-baselined exactly the same, then the results would stand a lot better than now. If the base line had moved up, then the results would have been less conclusive, if the baseline had moved down, then the results would have been even more pronounced. But we'll never know.

The point about how much time it takes to install the AGS, and to return to stock has two consiquences. The first is that time between the tests for all the other intakes are shorter. Here's your test methodology from your article....

1. Take the MINI on brief drive to bring it to operating temperature.
2. Roll the MINI onto dyno, pop the bonnet, and position a large fan to properly feed the intercooler with ambient air during the test, thereby preventing heat soak.
3. Reset the ECU by leaving the battery cables disconnected for 5-10 minutes.
4. Start the car and make the first two dyno pulls with the stock MINI Cooper S specifications, as a control data set.
5. Turn off the vehicle.
6. Install the intake system to be tested.
7. Reset the ECU again by leaving the battery terminals disconnected for 5-10 minutes.
8. Start the car and make two dyno pulls for the installed intake.
9. Take the car on a brief test run to evaluate driveability and real-world performance potential.
10. Go back to step 5 and repeat the process for each intake.

By doing the drivability test after the dyno, and then changing intakes and re-installing, you give the time between test more leverage in influencing results that had you done the drivability test before the dyno run. If you'd done step 9 before the dyno, you'd have a better chance of getting the car into identical measurement state for the dyno runs.

Now while many may be reading this as a flame, it's not intended as such. It's an objective critique of experimental technique. Any and all can agree with me or not, or chose to learn something about measurement technique or not. The whole point of my comments aren't to say the work sucks, but to say the work is good, but could be better. If you or anyone wants to do better measurment, here are some suggestions about how to improveme the experimental technique to get better numbers, that have higher confidence.

Matt

 

But it also states:

The two statements above make it look like the Helix/RDR intake came first, when in fact there were lots of intakes (Alta, BMP Design, K&N Typhoon, Pilo, Pipercross and Rogue/Madness) that were available before it

 

good job and thanks to all who contributed to this project.
youll find nothing but positive kudos here.

 

I'd have to disagree with this. By resetting the computer right before the dyno test takes place, some of the variables that can be created by the computer have been elimitated.

Say you hit traffic on one of the test drives, or EVERY light is red. Then on another test drive, you hit no traffic or red lights. Would this affect the results? We don't know, but it doesn't matter as the computer was reset before every dyno run.

 

But the ECU does a lot of changes based on things like coolant temp etc. You can read about all the stuff Motronic systems do if you like, but a computer reset without having coolant temps etc the same won't give you the same readings. Some of the observations other have made about the torque curves of the stock vs others at lower RPM could be explained by this.

Really, the answer to making sure that the car was in the same state lies in other types of data logging. They types that the measurment team chose not to do.

Matt

 

I guess the question is - did Step 1 take place (or some form of it) after each intake installation?

Dr Obnxs - do you have a link to anyplace I can read up on Motronic?

 

If the computer reset with a different set of initial conditions, then you could have the same or possibly worse variation in the computer's initial conditions than any variation in traffic or driving conditions would produce.

Edit: Whoops! Dr. Matt beat me to it!

 

Gasoline-Engine Management: Motronic Systems by Robert Bosch GmbH Got mine on Amazon....

But one thing is for sure, there no place that I've found yet that explaines all the mysteries of just what is and what isn't used in OUR systems. Kinda makes getting full knowledge a *****....

Matt

 

I want to understand why this is the case - do you have any web pages where I can read up on the systems?

 

Thanks!

 

I've seen dyno pulls at Helix read 15% under for the first pull, then typical (100%), then within 5% for consecutive pulls IF IAT is kept below 135deg F (exact # subject to my faulty memory) by waiting for the engine to cool down between runs, maybe 10-15 min with a fan on it.

 

Well, not sources myself. But the good doctor supplied a good one. What I do know is that it's an adaptive system that tries to reach optimal efficiency and power based on an averaging of conditions. Hence if you drive your car hard more often than not, the system will learn this, and optimize conditions for that average. But when you reset the system, there is no average to measure by, so it sets system defaults based on initial conditions, such as coolant temp, oil temp, pressure, octane rating, etc. etc. etc., whatever it's measuring. I feel that this is a large part of the break in time recommendation. It gives your cars system time to learn the environmental conditions that it will be driving in to optimize for where you live.

 

Interesting - I would have thought that there is a pre-programmed default setting that is then modified by driving the car. I'll have to read the book that the Dr recommended.

 

It's possible, but I'm pretty sure that it reads and makes up it's mind. That makes pretty good sense as far as the break in procedure, and the variation that can be seen by resetting at different times.

 

Just want to say thank you for the effort that went into this.

 

i have never heard of a doctor of photography. Is this a new title I am unaware of?

 

What? Dr Obnxs holds a doctorate in Physics if I'm not mistaken. I'd say that's one we've all heard of.

 

[quote=RallyMINI]There is more to car modifying then just HP numbers. Engine response, engine noise, looks, and other things. [/quote

I don't agree at all. "ENGINE MODS" are about engine performance enhancements therefore it is only about HP or TQ (engine response is a component because it is an performance enhancement) but looks and other things that have nothing to do with performance enhancement engine mods.

Example - lets say we have a pulley shoot out and a bunch of pulley are tested (all the same reduction percentage and the same price) but one manufacturer's pully is polished aluminum and the others not - using the methodolgy of the CAI shoot out that would be the winning pulley. BUT the proper conclusion from an engine MOD perspective would be that they all performed equally. A footnote that one pulley has a sexy finish is added information for the buyer but a none factor in making any conclusion about a performance mod.

While I commend the effort the articule for highlighting all aspects (pros & cons) about each CAI (in my opinion very well) as well as the graphs but the conclusion goes astray. The proper conclusion should have been along these lines - IF HP is your primary goal then X, if ease of installation is your primary goal then Y and if looks is your primary bag then Z.

 

It describes what Motronic CAN do as of 2003. But not what our cars actually DO. But my god, these little computer can do lots of stuff! It's pretty amazing. The only way to really learn what our cars actually do is to get in touch with either Siemens or Mini, and have them "open the skirt" so to speak.

Matt

 

Thanks for the response. I really feel that this is an interesting topic honestly. For you, HP may be the main goal. And in the example you give, you are right HP is the main characteristic since it really doesnt change the noise or anything. But concerning CAI's i believe that you have just stated your opinion. I know of people who have chosen their intake strictly based on the noise, and i know of a few who really just wanted red in their engine bay. The fact of the matter is that not everyone wants strictly horsepower. When it comes to intakes, the HP gain can't compare to a pulley. The numbers are all rather close, so i think that the noise, and aesthetics have a lot to do with the decision for some people. I respect that you arent interested in those things....i don't even care what my intake is gonna look like. I do however value HP numbers and really do look for the right sound. Everyone values completely different things. The aim of the article was to present the MINI community with enough information so that anyone could decide which intake they wanted based on whatever they were looking for. MR. Smith may want a nice noise and cheap price for his weekend car while Mr. Johnson may want the highest possible HP and TQ for his track car.

In terms of the conclusion...its strictly the conclusion of the writer. This is not meant to be a universal conclusion that fits everyone. Its also not as simple as "If you like noise, pick A" , "if you like HP pick B", "if you like easy installation pick C". People value each thing differently. I would say that i value HP 75% and noise 25% while the rest are 0% because i dont care about them. Mr. Bob may feel that noise is 75% and HP is 25%. How would you take all of the possibilities into consideration? We felt that offering all of the information would allow people to conclude for themselves by using the information in the article (and info found from other owners). It's very hard to get to the base of human reasoning far enough that you could offer the conclusion of every single human being in an article. There is a lot that goes into a decision, and its different for everyone. So we invite all of you to draw your own conclusion and buy exactly what is right for you There is a reason that there is chocolate and vanilla ice cream everyone has different tastes. As long as you choose what you want, you can't go wrong.

 

Thank you buddy

 

Point out that my degree is in shovelling "Piled Higher and Deeper!"

Matt

 

Here we agree, I find the topic interesting as well. It is always interesting to see what influences a buyers decision. I also agree that different factors come into play with diffrerent wieghted percentages. SO maybe 75% you and 90% for me but my point is if we are talking performance MODS the larger % of the decision making factors will be the performance aspect. I just felt the articule watered down the performance percentage too much (i.e. not the dominate % (less than 50%)).

By the writer determining a "winner", you typically agree or disagree with the writer and there my thoughts on conclusion eliminate that. At the same time my way of concluding the articule requires that you read, interpret, THINK for yourself and formulate your own opinion. I admint this does nothing for the sheep.

On the positive side the writer was very clear on the methodology used. Methodologies are neither write nor wrong but the basis for a conclusion or point of view. I just think again that he strayed from the performance mod target audiance (i.e. not less that 51% on the performance aspect) That doesn't mean that I discard the meat of the articule.

So whats next ? May I suggest ECU remaps, to my knowledge its never been done before.

PS - it would be great if you presented an overlay graph of the 3.

 

I'm with -bulb:
"Just want to say thank you for the effort that went into this."

salve for the sore knuckles.

 

thought I had a PhD living in my apt building one time; he had the gall to post a note and sign it "Joe Blow, phD"

found out later that he lived in penthouse D.