RE: giantscaleplanes (GSP) P-40 Warhawk
Snappy is an indication of an AFT CG. I would suggest you recheck that first. If it seems ok.. make it a little nose heavy.
Nosing over is more a position of the gear than any thing else. Some planes like the Spit and P40 are more prone that some others. There are a few things u can do to help. Make absolutely sure you wheels turn freely. You can also shim the rear of the retract to move the wheel hub a little more foward. Don't forget the Full Up elevator on the ground at all times. Hope this helps BobH.