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Old 01-29-2006, 01:30 AM
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Question and comments from Alta MINI Performance:

Originally Posted by John Herring, Alta MINI Performance
Thank you very much for the opportunity to participate in your intake comparison.

We are excited to hear that our intake system was deemed the overall best choice! Please let us know if we can participate in any other upcoming tests of similar items such as exhaust systems, headers, etc.
You're welcome! Congratulations on your victory, we think it is well-deserved. Thanks for helping us out!

Originally Posted by John
A few questions about some of the testing methods and procedures:

1) Why weren’t more runs completed with each intake system other than just two?

Common practice is to continue to make pulls (or runs) on the dyno until the results stabilize and or taper. One reason for this is to insure the engine and related components have warmed up to its optimal operating temperature (this includes coolant, oil, manifolds, SC, intercooler) and beyond where power starts to drop slightly. This method finds the optimal coolant temp to run the future tests with. With past tests we have done independently and tests performed by other forum members, the cars liked a warmer coolant temperature. This elevated temperature is achieved through at least 3 runs and isn’t available with only two. Resetting the ECU between runs may further exacerbate this problem, as two runs may not be adequate enough time for the ECU to re-learn and perform properly.

Please see results posted from another independent intake shootout:

Please note that each intake gained power up to the third run and beyond. We feel all of the intakes involved in your test could have performed better if a third pull was allowed.
This was due to the overwhelming response from the MINI community, who were kind enough to join us on our Dyno Day. To add another pull to each test would have required us turn people away from testing their cars, and since we were interested primarily in the differences between the power produced by each car (not just the total gains), we felt it was best to perform two dyno pulls per intake.

Originally Posted by John
2) Why do the results obtained for this test reflect dramatically lower numerical gains compared to previous tests?

The spread is so small between each that some might conclude that the differences are insignificant. Other tests have shown higher gains over stock with each of these brands of intakes. Most also showed larger gains between each brand (eg brand x made 8 HP gain, brand y made 14 WHP.) Going specifically to the ALTA™ Performance Intake with Silicone tube our testing reflects 12-15WHP gains. This is consistent on vehicles with and without S/C pulley upgrades. Additionally we have an overseas reseller that has the same Dyno Dynamics dyno used in this test, and it too shows a 15WHP gain. (Please find the attached dyno plots for reference for both you as well as your readers.) Again, the reasons for the low gain numbers may be explained away to both the two run maximum test length and the ECU resets between each brand.
Again, our primary interest in conducting this test and delivering this article was to serve as a comparison between the three intakes, not simply to reveal the gains produced by each intake. Production tolerances, both in the MINI and in the intakes, may explain why the raw numbers varied when compared to other intake tests. As with anything other parts, and any other genre of automotive performance, your mileage may vary.

Originally Posted by John
3) Why are the base HP figures so much higher than competitive tests?

While we agree that each dyno reads differently, operator error, atmospheric changes etc. it still doesn’t explain the extremely high base number. It is very difficult to hypothesize what the answer is, it is a good idea to point this out as well. If you or your staff has an explanation we (and your readers) would certainly be interested.
The answer to this question is a bit difficult to discern. We were also impressed with the high base numbers on Hollis' MINI Cooper S, but we also knew that this wasn't the first example of a MINI (or any other car, for that matter) exceeding the horsepower and torque numbers cited on its factory specification tables. Compared to other pre-'05 vehicles that were tested on the same day, Hollis' car produced anywhere from 8-12 more horsepower, stunning us with its surprising performance.

What else can we say? Hollis got the pick of the litter.

Originally Posted by John
Again, we do not mean any disparagement to the efforts nor to the recommendations made by the testing. These questions are posed to the potential benefit of all our competitors and readers. Simply put, it is vital for any comparative or technical information to be as accurate as possible so that conclusions drawn by the reader can be used to make a truly informed purchase decision.

Thank you again for inviting us to participate in this comparison. As stated previously we certainly welcome any opportunity to participate in the future.

John Herring
ALTA Performance
Agreed--we also feel that peer review is the only way to ensure the accuracy of our results, and we welcome readers, shops, and tuners alike to find out first-hand the benefits that a free-flowing cold air intake an bring to their own MINI Cooper S.

Thanks again,

Ivan Diaz
m|u Editor-in-Chief
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