Do you know how you want to modify them?
Unless you are a genius, I'd suggest going the easy route and buying the Tyga / HRC ones.
The alledgedly improve the power delivery by maintaining the velocity of the intake charge.
They aren't expensive, and I have them on mine, but as for measurable difference? I dunno, they went on whilst I de-restricted so it's impossible to say.
Matt?
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MC21SP Plaything
BMW F800GS Bumblebee
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