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      08-17-2011, 11:42 PM   #35
kitw
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Drives: 2015 MW M3/2014 Boxster S
Join Date: Jun 2007
Location: Bay Area, CA

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Quote:
Originally Posted by swamp2 View Post
Call me a skeptic, but that is one of my jobs around here... This sounds like a systematic error rather than power gains...

1. Either the engine adapts immediately to the mods or doesn't.
2. If it does it should not continue to make more power each run. Thus the conclusion is bad dyno results.
3. If it doesn't then you could only see this if it adapted very quickly.

As is typical - there are many ways to spin dyno data. It is often as good as we want it to be when the levels are basically in the noise. We would not be having the discussion (well... unfortunately we probably would be..) if the claimed gains from another modification, say modification "X", were dyno proven to be 2-3 hp.
actually, no this isn't true. You'll find that the car won't adapt immediately, especially if there is no closed loop operation between installation. I would expect that if there was a significant change in airflow that it would take a few pulls for the DME to fully adapt... it should continue making power and plateau.

That said, I'm very skeptical, I just can't see the stock intake tube being a restriction. It has what appears to be a very large cross section, with smooth bends and a very small accordion section.

Scoops, as well, I can't believe. Even if they did manage to somehow pressurize the airbox, the fact that it is open no only to the brake duct (which is probably a low pressure area) but also to the hood vent (also a low pressure area!). I actually think that due to the drastically reduced airflow on a dyno, vs out on the highway, Scoops may actually perform in dyno conditions, definitely less low pressure in both the brake duct and the hood vent.

Anyway, I did notice a small amount of power from my AFE intake (which is really poorly designed because it uses a smaller than stock filter!) so maybe I'm on crack and there is power to be had. I pay people to tune my car and make parts because they are a lot smarter than I am. (although weeding through the noise is hard sometimes)
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