i am planning to do stacks among many other items. question is whether or not 6" stacks will help or hinder performance. game plan is to follow through bed with 4" then "Y" off coming across to adapt to the 6" stacks. provided i can find the appropriate connections.

or is there a more suitable application. only reason why i choose the 6 inch is for looks.


THANKS ALL FOR RESPONSES

 

If it is just for looks, you could fab-up a 4" or 5" internal pipe, with the 6" stack as a heatshield/cover. I have thought about this too, since I don't want to melt things I carry in the bed. I think the chimney effect of the cool air rising along the internal tube might help keep the outer stack cool enough...

Just thinking out loud.

 

From what I understand from gathering opinions from several sources, going from 4" to 6" pipe/stacks will cause a lot of turbulance if the transition is too short, which may create excessive back pressure. Now the idea of 'hiding' a 4" pipe inside a 6" stack would get you the appearance you want without the risk of creating excess turbulance, not to mention should look very clean.