Originally Posted by Mechie3
Does this mean it's not good for a daily driver?
What sort of problems have developed?
I've had this part installed on my 05 STi for about 6 months and about a dozen track days and I can attest to its benefits big time.
However, there was a problem with the shaft hitting a point on the floor board right in front of the rear differential. I was lucky as I inspect the car after every track day including putting it up on a lift and that when we discovered a groove on the shaft from hitting said point on the floor. Gone unnoticed I'm sure it would have destroyed the shaft ultimately.
We think that as the car flexes during high speed cornering, accelerating and under hard braking while on the track, there's some "play" that allows this to happen. It couldn't be anything more than mm's as the groove is pretty tiny and shallow but it's there. So we pounded the floor boards a bit, used a Sharpie to color the groove and so far (knock on wood) it has not re-manifested itself after a couple of track days.
Other than that prepare to be amazed as to how quickly the revs get up. And I'm only a AP Stage 2 (though with meth) with a catted DP even.