Hey i am wondering what size pipe would work best for true dual straights to create enough back pressure.. any help or suggestions would be great

 

I have true dual with 2 inch it has enough back pressure sounded good when i had no mufflers

 

do you still have the 4 cats on there.. or?? and did you put them straight out or side exit?

 

I still have all four cats and had them at a 45 degree angle 3 1/2 inch rolled tips

 

I have a 4.6 with a K@N and 2, 18 inch magnaflow mufflers with a x pipe. Running 2.5" from the cats back. The piping in and out of the cats are 2.5" so I kept running it back. No check engine lights, runs and sounds great. slightly less back pressure.

 

Back pressure is a myth theres a sticky on here with all you need to know about exhaust

 

2" is good to keep the back pressure and still have added hp but if you have a bunch of mods to your engine go 2.25"-2.5"

 

[QUOTE="Tonelocs47"]2" is good to keep the back pressure and still have added hp but if you have a bunch of mods to your engine go 2.25"-2.5"

Forgot to add make sure to get an x pipe not an h pipe, more torque

 

Use at least 2.5" piping, no less. Backpressure is myth...

 

[quote=Tonelocs47;1148970]Please read: https://www.f150forum.com/f11/exhaus...re-myth-78102/