Join Date: Feb 2007
Location: Pittsburgh (Oakmont)
Exhaust with Clayton Back Half
I had heard that I would need to do some exhaust mods to get the Clayton Rear Long Arms to fit, but figured I could at least weld the brackets on. Well, I was wrong - I have a Borla cat-back and discovered that the brackets interfere with the Borla muffler. Since I have to replace some parts anyway, I thought I should keep the Borla catback intact and build something like I had seen others build. Specifically, a shortened assembly of the cat & muffler with a turn-down before the rear axle.
So I went to measure up what was under there and found something odd. The pipe going into my main cat is 2.5", but the outlet is 2.25". This is the factory cat. I've heard that some back pressure is desirable for low end torque, so wondering if that was the reason for the step down. My question - if I go all 2.5", am I going to lose power? Only have the 4.0 - stock 3.55 gears with 32's. It's just acceptable now - don't want to make it worse.
The thought was to replace the OEM cat with a Magnaflow 2.5" in/out and a 2.5" in/out muffler.
2000 WJ Laredo 4.0 4x4 Taupe Frost - Stroker | Clayton LA w/3" Lift | 33's on JK 17's | Axles next