[jerry56]

Hmmmmm.
with 1 and 2 slaved +100 and -100 any change will affect forward and reverse ( I assume)
You could try changing 2 to -50 just to see what happens or maybe adj the power curve to come in slower...Are you using a flysky radio...?? I wonder what the "elevon" setting would do for ch1 and 2...or the dual rate for ch 1 and 2... I'm not well versed on the finer points of theses transmitters. I've only done the delta loader and D5 conversions both are tracked the delta turns pretty fast but that's how they are in real life... the D5 probably does too but there is enough track slip in the dirt that you don't notice it....
I think the "elevon" settings might help because I think they are to help to control turns.
You need an airplane guy to step in here ....