ive been reading alot on this subject and im wondering what is the difference between a stock cat converter and an aftermarket one (magnaflow) or any high flow cat converter. i was wondering if i were to get this replaced would this set off my check engine light. another thing i was wondering is would this increase hp and or gas mileage? someone please fill me in on the pros and cons on this subject. i live in pa, im not worrying about failing emissions because i can still get the stickers when needed

 

A high flow cat could set off your check engine light. If you have emissions testing you would need to either have the PCM re-programmed (code deleted), or do the anti-fouler/plug-fouler trick and get the rear sensor out of the stream.

There probably will not be any significant hp or gas mileage improvements. You might notice a slight change in the sound of your exhaust.

 

As 01 Monte ss stated it will set off the check engine light more than likely. The only reason a high flow cat is needed is if the exhaust is to restrictive do to the mods you have done and that takes a lot of mods lol

 

Ok so I guess I'm not doing that mod then. Lol but if I get magnaflow mufflers would that make a deeper soind atleast?

 

its hard to get a "deep" sound from the 3800 engine, at idle its possible but once you start accelerating it will get raspy IMO.

go on youtube and watch some videos of 3800 exhausts and see what you like is the best advice i can give you.

 

It seems like most that have problems with setting codes are those that installed ZZP, Hogan and various other aftermarket replacements that do not meet OE specs. Increased downpipe diameter (reduced exhaust velocity) and universal cat converters are a definite recipe for problems. I installed a Magnaflow downpipe w/cat about 1.5 years ago (that meets/exceeds OE spec) and have had no problem at all setting codes.

 

idk, i think i might just stick to aftermarket mufflers....the check engine light is the last light i wanna see on my dashboard