... did not weld up that recessed center exh. divider? Just curious.

Also curious on any 'sound difference', as well as cons of not doing so (other than blowing out that exposed piece of gasket material if you did not cut it out beforehand). tx

 

I never filled it, and mine still sounds like a tuna boat.

There is a definite tone difference when the crossovers are filled, and the divider is welded......but if the xovers are not filled, i don't think it's going to make a big difference 1 way or the other.

 

i never welded up mine and i also never blew out the center piece of gasket i used the felpro blue header gaskets they never blew out

 

I never welded mine up, I have run them with block offs in the heads and without. I can't give you a before and after on that. It was always done with a rebuild. My gaskets only leaked when the bolts backed off.
I use the copper header gaskets now and do not have any problems. Well other than my 15 year old headers now rusting out. Time for new...