I just had the pipe from the end of the cat and everything back replaced. Now the pipe in a diagram I was looking at coming into the muffler should be 2.25" then 2" dual out the passengers side. Well the muffler I have now is 2.5" in and dual 2.5" out. Would this effect me any for the worse with a V6?

 

Shouldn't think so.

 

Yeah I was thinking it wasn't too large. At most it made the tail pipes 0.5" larger and considering most of the larger diameter is at the end of the system I guess it would not matter.

 

2.5 is just perfect. If only your ENTIRE system was 2.5 inches! I wouldn't go higher than that though...3 in. robs too much torque and low end and messes with the power curves.

 

where is this "back pressure" force applied to ?

the vavles ?

from the converter forward ?

from the muffler to the tips ?

 

I always thought it was applied to the cylinder where combustion occurs but I wouldn't really know, that's just a guess.

 

Simply put
Back Pressure
Torque
Push ya back in the Seat Stuff!
2 1/2" in & Out CC
2 1/2" Intermeidate Pipe
2 1/2" in to two 2 1/2" out muffler tips to bumper.
Works just great!

EVEN BETTER!
Have remade your "Y" pipe. Make it a smoother connection & ya easily gain 5 HP & smoother runner engine.
Open hood look down engine passenger side see why.

 

Yeah I've seen that crummy Y pipe. It's like a 90 degree connection and I don't think that can flow well at all. If only I had tons of money then I could consider messing with the Y-pipe and cat.

 

Check, IT could be very inexpensive.
GAIN BACK REAL FEEL HP!