My best is a 13.6 @ 101 mph, which was run with no wing.

With the wing on, the best I can manage is a 13.8 @ 99 mph.

So if your car is weak like mine and cannot overcome the drag the wing produces, remove it.

It's a cheap mod (it will only cost the price of replacing the wing gaskets), but it is very effective.

I'd advise putting the wing back on if you do any sort of hard braking though. The rear of the car is noticeably more twitchy without the wing in place.