When I race the XRR and shift through the gears down to 2nd, I get a sort of stutter in the engine. I just wanna know whats that supposed to be, and if it slows me down. 
I took a mp3 of what I hear, you may try the set and check if it happens to you too.
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I took a mp3 of what I hear, you may try the set and check if it happens to you too.