x and h pipes

I have a somewhat hybrid exhaust on my 64. Hooker headers,2 1/2" summit X, dynomax ultraflo's and tti tailpipes. It sound good at idle and cruise. When you're in it, it has a higher pitched sound. None of my buddies small block cars sound like it... At the track it runs the same full exhaust or open cut outs!! On the dyno little change in hp but torque jumps about 30 ft lbs open..

Bob