Not sure! When I had the GMS, I was using an HPP at the time also. I didn't use the HPP tuning with the GMS, just the shift points. I like my Predator and don't know if it's tune will get along with a GMS or not. Seems like a waste to have a tuner and not use the tune.
Jim

 

Im about 15 minutes from concord, when this guy knows how to use the dyno, get a price from him per pull

 

You got it!
Jim