Engine cat back exhaust , performance exhaust , catalytic converter

not to mention that replacing your cat unless you have 50k miles or if it is bad is illegal, but running no cat makes the exhaust sound so sweet

very true about the cat. my friend has an 65 mustang and we are running straight pipes on it since we dont have to pass the emissions test. holy shit that sounds nice.

cat back exhaust , performance exhaust , catalytic converter

some1 explain the differnce between these systems im confused about them

ok.

a cat back is larger piping from the catalytic onverter back. usually about an 1.5 inches wider. it allows for more flow, which means more power and usually a better exhaust note. can be very expensive

a performance exhuast i guess is just a bolt on from the muffler piping back. or it welds on. wont give you as much performance as a catback.

a catalytic onverter is the "filter" that allows your car to pass its emissions test. with out it it will fail. it robs you of hp.

excellent summary mike, as far as the cat converter-replacing it really depends on the engine your runnin and the overall power output-if its like a slow ass 4afe like mine-then replacing will w/ a high flow version will just kick you in the nuts and you'll lose lots of low end power- and not to mention that if your a tree-hugger, then you'd be polluting the environment...

I was running a no cat but my CEL kept coming on but it did sound nice specially when idlin with a rumble going on...blah stupid imports and their sensors pfft! but yeah Mike did a good job at explaining the whole exhaust system..if u can get rid of the cat by all means go for it that little crap is a theif of ponies.

How much low end does it rob though?

all of it. believe me, once you try it, you will know. i had a header, resonated test pipe (labeled a hi-flow cat), and muffler. granted, i still had the stock midpipe, which was kinda small, but with 17's, i got my ass whooped off the line every time. there's just not enough displacement in our engines to necessitate the use of a straight pipe unless you're runnin boost or nitrous.