I have an 86 bullnose with the 4.9 L6. Im most likely going to use the stock exhaust manifold with a Y pipe. What would be the best piping size to run and with what glass pack. Im wanting to either turn out before or after the right tire but not sure. Was wanting to split from the glass pack into dual tips but didnt know how good that would work.

 

I hate a glasspack on a six. Sounds like a ricer, and I hate their sound too. If that's what you want, just replace the muffler with the glaspack and route it anyway you want. A larger pipe size won't make much difference on that engine. It's probably 2 inch now, and that should be fine for it.

 

Had a Thrush glasspack on my 300 that me and my friend hollowed completely out. Burned the glass and removed the metal tube that holds it inside. Sounded pretty good. Deep sound when you short shifted it and got on it. I think it had 2 1/4 pipe without a cat on factory exhaust manifold. Swapped for heddman headers and dual 2 1/2 pipes with 10 inch glasspacks that were burned out also. SUPER LOUD! Switched for dual flowmaster 40 series. Sounds great any way i drive it.

 

just stay with the stock exhaust why reinvent the wheel