catalytic converter

Has anyone have experience with removing the second cats?The sensors O2 are for and aft of the primary ones. Will the loss of backpressure cause issue? Any information will be helpful since previous owner replace exhaust with 2" after cats

 

URD sells a Y-pipe with the 2nd cats removed. Doesn't cause an issue.

 

What about daily performance/driveability with removed? What is the purpose of them??

 

Secondary emissions cleanup. It is technically illegal to remove any emissions control device, so factor if your state does inspections and how thorough. With them removed it will reduce back pressure, which in theory leads to higher performance.

 

Thank You. I guess technically they can get plugged. 103k on a 08 4.0. I'm not charged yet, but debating. Stock, it doesn't come on until 2500rpm.

 

Backpressure is never good, and that reducing it can cause loss of power is a Fast & Furious, "magazine mechanic" myth.

Read more here, and here...

 

agreed!

 

had the rear 2 removed on my last 2nd gen, 2.5" y pipe, 3" outlet after the muffler, no loss/gain in power (All SS Mandrel bent). slightly different exhaust tone,
IF you have the skill to build an exhaust system, ya might go ahead and removed them just to start the exhaust at a new flange to clean things up. but i could not justify the fancy y-pipes from any company unless you were running boost. Exhaust re route for clearance and slap on whatever cat back/muffler you like and call it a day.