Inductionkits works if:
The internal restrictions in the airways are less, than on the original.
The new inductionsystem has less/softer curves on the pipes, smooth internal surface, no sudden variations in diameter, and has the correct wavelenght design (giving optimal pressure at the valves (a compromise, no matter what)).
Factory inductions try to get it, but they have to make compromises.
Firstly, cost of manufactoring.
Invironmental demands like noise levels.
From where to get the fresh air (the enginebay is NOT EVER an option)
Placing an airbox on top of an engine is not a good design, but often used = easy and cost effektive = factory earnes more money pr. sold car.
Placing it next to the engine, preferably separated by a little wall, would be much better.
But then access to the filter would be even more restricted than getting to that idiotic oil-filter.
To make things fit in the engine bay, factories change the shaping of the piping from round to flat to square to oval to round and so on.
And they connect it all with different types of flexible rubber elements.
Optimally it would be one precision shaped pipe of equal or slightly groving diameter and with only few and gentle bendings, all the way to the filter.
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On my V6 (Busso), the airfiltersystem is downright made by idiots.
From a factory standpoint, its not even a good system.
It's complicated, difficult to assemble on the construction-line and difficult to service later for the owner/garage.
(And DONT mention the oilfilter !!!)
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