Hi, I have a totally standard 2002 bugeye wrx and have noticed that when I depress the clutch to change gear it goes up by about 200 to 300 rpm before it drops and am a little concerned because all my other cars the revs drop immediately, is this a normal turbo engine thing or do I need it checking out, thanks in advance, Andy.

 

My STi used to do this. It then got worse and was revving while off the throttle. Turned out to be the idle control valve.
Cleaned it and no more problems. Might be a similar problem.

 

I'm getting exact same problem and thinking its my clutch. The bites right at the top so disengaging that split second early when accelerator not fully released yet, if I leave a 2 second gap between gear changes the cars fine.