Re-thinking this whole CG thing.........

Guys I got tired of fighting the muffler problem and put a Pitts style muffler on the Tower .75 as others have done. The plane flew absolutely great untill I tried to land. When I cut the power it dives for the deck like a thirsty earthworm. I managed to save the plane, I made a go around and tried to control the landing but it hit hard and broke loose one of the main gear mounts. It bounced and I mean high and the prop was damaged in the intial hit so I was committed, I pointed the nose at the ground and gave full elevator before impact and it settled on the runway light as a feather...got a standing "O" for that one. With the Pitts it changed my CG to about 10.75 so I am wondering if this behavior might just be the Bobcats way of letting me know its tail heavy. The only thing is I would expect it to mush and tip stall instead of dive for the deck and it shows none of this behavior at speed???? Maybe this is a jet thing, this is my first Jet type glow model. Any input is appreciated.

Gotta go buy some more underwear.