Subaru STi MY08 XA Power Kit

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Below is (un-edited) feedback from a happly client who had the MRT XA Power kit fitted to his Impreza WRX STi.Hi Mr. Middleton,It’s Charles here with the ’08 STI. First off with the XA kit, I think you would probably be happy enough to just hear that I love it, but I guess I will share a little more than that just to make me sound a little more knowledgeable on cars than I really am. It is absolutely flawless in all departments, as in the engine now feels better in every aspect compared to before the XA kit was on. There is no tradeoff there like I have to sacrifice peak power and torque for response, or vice versa.The increase in power and torque is noticeable but what I enjoyed the most is the quicker and sharper throttle response. The Intelligent Mode on SI Drive is more engaging than ever, whereas in the past I might even stall the car from stop sometimes on I Mode because of how slow the throttle response was. The improvement from the XA kit wasn’t only just to make the car sportier, but also making it easier and more comfortable to drive when in city traffic, like what I said before there is no tradeoff in any aspect of the driving experience. The engine when disengaged from the drivetrain and dropping to idle is another interesting improvement (?) I found as in the past the engine sort of surges back a little after reaching idle speed (maybe it’s just me), but now it just drops and settles to idle.I haven’t fully tested the car out on a more “demanding” road, but from what I felt from shifting at high rpm on a straight road, the car doesn’t feel like it’d need to pull again to climb back into the power band, with every shift it falls right inside the power band. I really do appreciate the effort put into the developing this kit as it is tuned to suit the gear ratio as well, and not just increase torque and power to look good in figures. I think the magic of the XA kit is not in the advertised kW and Nm increases, but in the total balance of the car.If I find more things to rave about on this upgrade after I give it a few more runs I will definitely report back. I expect cornering to improve as well from the quicker and more delicate throttle response.Thanks again for this wonderful tune, I will drop back if I need anything more in the future.Regards,Huang CharlesRead more client feedback here