Ok I was the most performance out of my exhaust system. So Far I have the headers on my truck and now its time to work my way down the pipe. I have 2 precats with O2 sensors after them, then the two pipes merge into a single cat (all with 2.5" pipe) then the pipe shrinks to ~2" pipe and goes to the muffler and over the axle and out behind the tire.
Now for maximum Performance gain, would it be better to cut off that cat after the O2 sensors? Would it be better to run the exhaust out before the rear tire and use 2.5" pipes? I can do true dual exhaust on the truck just by running the pipes side by side and taking out that cat after the sensors with 2.5" pipe too, or 2.25".
Or is it best to just upgrade the pipe to 2.5" and throw a borla ProXS muffler (the muffler id use on any set up) and follow the stock exhaust route?
Current :-: 2004 F150 Lariat 5.4L 3V | Whipple 8PSI | True Dual Exhaust | 14.5 @ 93.3 (Quarter throttle launch due to horrible traction)
SOLD :-: 2004 Ranger 4.0L XLT 2WD | 4.10 Limited Slip | K&N Intake 63 Series | Borla Turbo Muffler | JBA Headers | Data Logged XCal2 | 2003 SVT 18x9 Rims | 255/55/18 BFG KDW2