Well, I run a TurboXS RFL and hks eids with much success, but today, after a hard run it would stall and barely move. So I stick my finger in the trumpet (:brows and "SNAP" it back into position. It had gotten stuck wide open. When I got home i took it apart and saw several wear marks on the, what I assume to be, brass piston. Hopefully it doesn't happen again. Just a headsup, as this is the first time I've heard of such a thing.

 

I would recommend throwing just a tiny bit of oil on the piston so it doesn't get stuck again.

 

Try adding an add'l washer or two underneath the spring. I had to do this with the provided washers to my rfl on my old WRX. Try it and see what happens.

 

I had that problem on my Eclipse. I put some grease on the piston, and the problem went away.

 

Yeah you have to grease them every now and then.

 

I'm currently running 2 springs, but it flutters at light throttle in 5th gear. I'll put 4 in and see if I get surge.