Thanks scott I on that problem still I'll post it when i get running. I remember all I needed to do was put the advance timing to 12 to 14 degrees? I'll try to do it tomorrow sunday and I will PM with the results  

I had a '67 Chevy truck with a 283 that I put dual exhaust on, exiting both sides in front of the back wheels.  On more than one occasion I was accused of having a six cylinder by people standing next to the truck.  The sound was so separated that people only heard the one bank of cylinders.
Just a thought.  

is that because with the dual exhaust on a 283 did not make back pressure? or why? Beacuse I have a 351 and having pipes not bigger than 2.25 to 2.5 (i heard) give me enough back pressure and HP I guess. I was gonna put 3 in all the way but I was advised not to.  

I would guess the six cylinder sound would have been a combination of cam and hearing only half the cylinders on one side of the vehicle.  Probably sounding like a big 4 cylinder, but no one in their right mind would believe that, a 6 cylinder would be the next obvious.

I agree with not going with the 3" exhaust.  Unless built and tuned for it the engine could easily burn an exhaust valve. They get hotter as back pressure decreases.  And the smaller pipes help build torque, where as bigger pipes than needed don't build Hp and definately hurt torque.