Exhaust advice..?

[rivbro91]

Hey, Got a 99 hoe. Was wanting to delete the cats, cut the muffler off, and dump it right behind the rear axle. Will i have hell with the rear O2 sensors. or will it just display the svc engine light, or what else could possibly happen?

i love the sound of flowmasters but everybodys got em.. and i wanna be different? any advice (i hate glasspacks)

 

[95TwinTT]

Do youself a favor and leave the Cat's in place. The only thing in the exhaust slowing the flow would be the muffler.

If you want a great sound and free flow, look into the Hooker, "Aero Chamber". They will loosen up the exhaust for you and not screw up your ECU.

Flow Master uses the "Chamber" style that reduces the sound level without creating much back pressure. There are several other Muffler makers that do similar things. Aero Chamber is one. You will find some others, by using chamber, as one of the key words in the search.

Cutting the cats off the newer vehicles is just asking for trouble. If you had $25,000 or more tied up in engine mods and were reaching for big power, there might be a reason to loose the cats, otherwise I would leave them alone. Just my humble opinion. Good luck.....:cool2:

 

[rivbro91]

thanks

thanks for the reply, but cats don't have a very good sound imo. and im thinking about straights. i found a module that lies to the vehicle and says that the cats are there, when they aren't.

 

[GMCYukalade]

Ok.. listen - i deleted my cats.. and that is one thing you really do not want to do.. especially if you have the rear-hatch, and you leave it open some in the summer.. - and the cats don't have ANY effect on the sound - they are free flow - if they aren't dirty.. you can look thru them and see light on the other side... frrrree flow - - now after i deleted mine.. motor.. ya you would think this will be more hp.. its not.. its less.. SES light stays on.. and where i live.. you can not pass inspection also.. gas consumption due to the computer being confused all the time.. and trying to lean the gas, than when that doesn't work the computer will try to give it more gas... the pcm will constantly be trying to please those rear O2 sensors.. -- now.. if you do want a more free flow - get a set of FlowMaster Cats.. or something similar.. they will keep the SES light off, keep the PCM happy.. etc etc (or if you wanted to be more drastic spend a couple hundred on a tune, and have them delete the rear O2s from the PCM.. or buy EFILive which is a $749 option..).. or you could go the cheap way.. and leave the cats

 

[95TwinTT]

Amen!