High FLow Cat Or Not

[91xltTerd]

Does a High FLow cat actually help or hurt the performance of the 4.0 ohv explorers? I haved talked to several people who all seem to have different opinions. Some say it helps top end and hurts bottom end b/c of back pressure. If that is true I don't want one b/c I am looking for bottom end power.

P.S. my SuperChip is in the mail.

Chip

 

[AgExplorer]

What you have heard is true. You do need some back pressure for the bottom end. Most who have replaced the exhaust from the cat back with a performance set up have seen benefits. The cat is not very restrictive. It's the muffler.

 

[Ru Dawg]

Originally posted by 91xltTerd


P.S. my SuperChip is in the mail.

Chip

Ha Ha...Chip is getting a chip! sorry...couldn't resist!!
I know....very lame!

Anyway, I wouldn't mess with the cat, I'd just replace the cat-back with a good muffler. I have a Borla cat-back and love it! Lots more low end power and beautiful sound!!

Also...you're gonna love the chip!

 

[brax-91-xlt]

Originally posted by 91xltTerd
Does a High FLow cat actually help or hurt the performance of the 4.0 ohv explorers? I haved talked to several people who all seem to have different opinions. Some say it helps top end and hurts bottom end b/c of back pressure. If that is true I don't want one b/c I am looking for bottom end power.

P.S. my SuperChip is in the mail.

Chip

Hey I live in Mississippi where the emission standards are non existant. I've got no cat, a turbo muffler exiting at the original stock point. My Explorer sounds good as well as performs well in the mud. I've got very little backpressure and get good gas mileage. But hey man do what ever you think is best.

 

[91xltTerd]

I think I'm gonna go with the flowmaster 40 with a single 2.5in out the back and leave my cats alone for the time being. I might try to talk to the guy at the muffler shop and get him to make me a pipe to totally remove my cats that bolts on so i can see which way is best.