I've got an ahmed chip in mine and when jamie at Jamsport set it up he had to wind that much ignition off the engine(retard the timing), just to stop it detting. I had the same problem on my last one and when i changed to a superchip, you could actually advance the timing and get decent power out of it.

Needless to say when it has the cam and intercooler upgrade over the winter, it'll be having a jamsport superchip fitted and get some decent figures from it.