I've read through this forum and maybe I missed my answer. I've seen where several people have preached free flow exhaust, less restriction, better hp gains, better mpg, etc... (sounds reasonable to me).
What really got my attention was when I read some members warning of too little restriction resulting in a reduction of mpg.
How does back pressure effect mpg?
How does back pressure effect hp?
Where is the happy medium on pipe size?
My "later down the road when I have some cash project" is to put an after market muffler and keep the original exhaust pipe"
The factory pipe is 3+ inches. I've read optimum is under 3". If that's true, would reducing the pipe down to 2.5 - 2.75just prior to the muffler inlet solve this problem? I'm wanting to have a DEEP rumble and I don't want anything to disrupt the sound as it travels down the 3" pipe, but I don't want to reduce my mpg as one member posted with surprise.
Some one help me out here. Explain the science behind it.