I'm planning on begging the exhaust upgrades for my 89' Iroc. I've been doin reading and going through these boards and decided on the Hooker Cat-back and The Edelbrock TES headers system. I was going to not run a cat, and had a few questions. First What is the purpose of the air tube running down to the cat, and what should i do with it if running no cat? Next could I put a slip on y cutout and some 3" pipe in place of the cat, to both fill in length of the missing cat and allow me to open up the exhaust if i ever get to the track? I want a setup that would allow me to run like this, but easily bolt a cat in when i get called in for emissions. Any comments, suggestions, or help we be great, thanks
Josh

 

be creative... thats about all i can tell you

 

Put the cutout in front of the cat. Then you don't have to worry about the cat at all.

 

cutouts suck on anything slower than a 13 second car. They are a waste of time and sound like @ss.

I have one and thats my opinion of them.

 

thanks for the comments, im still confused about the tube that runs to the cat and what to do with it if i do go without a cat though

 

just run/weld the air pipe into your new exaust or weld it shut. or completely take it off if you dont want it on your car. it wont hurt a thing no matter what you do with it. mines been gone for years

i run a cutout before and after the cat. with it open before the cat you can hear more engine fire(popping kind of noise). the one after the cat has a more of a tone than before the cat. it sounds great. i wouldnt do the before the cat unless for the track. i run the after the cat one on the street.

 

dont pinch the air pipe off it will cause a noise in your air pump.
either take it out or weld it in.if you are going to keep your cat you need it to help emissions.it will pump air into the secondary bed and cause it to heat up to get rid of emissions.

 

Cutouts are awesome and they Do Not sound like ****...... Lowered my time by .3 in the 1/4, not bad for 45 bucks installed..... And that was with a plugged cat. I have not run it with the !cat

Will

 

So wouldn't it make sense to say that BYPASSING a clogged cat with a cutout was worth the .3's? The cutout wasn't responsible for the improvement as much as the clogged cat was killing performance.

 

I don't have a cat anyway, and in Cali its illegal to place it before the cat, regardless. My car still passes the sniffer with a hollow cat, so as long as they see one there, with nothing infront of it, its passes. Do you have some kind of grudge against cheap performance or what? Just cuz you don't like a cutout doesn't mean this guy won't.
I meant this as an example, that it infact helped over the the exhaust exiting the muffler. I've got time slips to prove it, so if it helps with a ****tty stock catback, then it must help with a better performing system. All the guys I know out here run cutouts, there MUST be something positive about it right?
Later

 

Here's where I mounted mine -

my cutout

BTW....cutouts sound good on built cars, not stock ones.

 

And my Cutout is mounted AFTER the cat, under the rear seats, so YES it was responsible for the .3 drop. By bypassing the muffler, it dropped significantly.

 

Thanks guys, im only going to be running the cutout at the track so the sound really won't matter i just want little better flow for a slightly more respectable timeslip