Green93

Hey guys, I just installed a new exhaust on my truck. It's the LCE Pro flow system and a cat delete(test pipe).

Ok, I have a couple of questions. First is the smell. I know that the cat burns off some of the gasses in the exhaust. But, without one on my truck I get ill when I drive from the fumes. Does the cat really do that much or do I have another problem going on? So obviously I need to install a cat. I don't want the stock one on there so I was thinking about using a hi-flow cat. What effect will a cat have on the exhaust sound? To be honest, my exhaust is a little too loud for me. I feel guilty when I start it up in my garage at 6:00 every morning. Will a hi-flow cat tame the sound? Are there certain brands that will do more for me?

Anyone have any before cat, after cat exhaust clips?

JAson

Jay351

Well, yes the cat will burn off excesse fuel so you won't get that smell.. But there might be another issue at play aswell.

Any hi-flow cat will offer a little restriction and tone the noise down a little.. Any one will do, try to go with one from a decent company (good quality). Or you will be replacing it soon.. *ahem, magnaflow ahem*

got a video clip?!

abecedarian

technically, the cat doesn't burn anything... it catalyses a reaction between partially burned hydrocarbons and un-used oxygen from the combustion process and from the air injected by the air-injection-reaction system into the exhaust manifold resulting in lower HC emissions.
anyways....

a high-flow cat can alter the exhaust sound if it is shaped in such a way, or is significantly larger than the OEM converter, that pressure/sound waves within it do not behave the same as the OEM converter. usually though, the effect is pretty small, resulting in a slight increase in the 'growl' or 'gurgle' in the exhaust.

874runnersr5

hmm i knew after replacing my o2 sensor it didnt smell that strong... but i still can smell it sometimes only when ihave the rear window down.

Green93

Well, I just got back from doing what I should have done in the first place. I took off the test pipe and re-installed the stock cat. The sound is greatly reduced. It loses that annoying snapping at WOT. Seems to sound deeper now, instead of that hollow idle sound it had before. If a hi-flow cat gives me a happy medium I think I'll be happy. I will need one with the correct radius though since I can't get this stock one to stop leaking. Probably a combination of the larger exhaust tubing and the re-used gaskets. Also, the nasty smell is gone from the exhaust.

So Jay, do you know of a place local that sells a bolt in cat for our trucks? I'm going to need one soon and can't wait for shipping. And were you recommending Magnaflow or not? My muffler is Magnaflow so I might as well keep it the same. You should stop by when I get the new cat. Before I put it on we can install the test pipe and I'll show you how it used to sound. No movie clips...I forgot.

Thanks for the help guys.

Jason

Green93

Sorry, forgot to mention the O2 sensor is new as well.