can you cut cats off and what will this gain or hurt

96 blz28 · 11-18-2006, 10:54 AM

I have a buddy thats might buy my car and he wants me to cut the cats off and straight pipe it

FS3800 · 11-18-2006, 11:08 AM

you'll definately see gains.. especially on the top end... but you will throw a code in your PCM... SES light on and all.. to fix that you'd either need to get the codes deleted.. not sure how that'd work with a 96.. or you could get a O2 simulator... but that could break down the line and need to be replaced.. if you can get those codes in your PCM deleted then no worries anymore

redneck01 · 11-18-2006, 11:39 AM

yeah those simulators cost about $80..you'd need a tuner to delete the codes though. the o2's just plug right in easily. will sound much better without cats as well.

2000GTP · 11-18-2006, 07:31 PM

Might get some gains, nothing tremendous though. You'll probably add alot more raspiness to your exhaust note as well.

Klypto · 11-18-2006, 07:56 PM

i gutted mine... didnt see any performance add, 13.5 before/after (not 100% same conditions though, was hotter after i gutted them) but id sounded deeper... which is mainly what i did it for anyway

cory

camamroz28fc · 11-26-2006, 06:01 PM

hey gutted my cats on my 01z28, and at the begining my car wanted to turn off is that normal or do u have to addjust it

2000GTP · 11-26-2006, 06:59 PM

Quote:

Originally Posted by camamroz28fc

hey gutted my cats on my 01z28, and at the begining my car wanted to turn off is that normal or do u have to addjust it

Taking off the cats isn't going to affect your engine in a way that it is going to want to shut off. There may be another problem you need to look into. However, if you take the cats off, you will set of the SES light. You can fix this by having the codes edited out of the PCM or buying a pair of 02 simulators and plugging them into the rear 02 sensor harnesses.

camamroz28fc · 11-27-2006, 06:41 PM

so if i get the 02simulators that would turn off the service light and would it run normal

2000GTP · 11-28-2006, 08:27 AM

Quote:

Originally Posted by camamroz28fc

so if i get the 02simulators that would turn off the service light and would it run normal

The 02 sims. will provide a "dummy" signal to the PCM that will prevent the SES light from coming on. You may still have to have the present code cleared though. As for the car running normal, the rear 02 sensors are going to have no effect on the cars drivability, you may have another issue at hand if you are having performance problems.

crushah · 12-07-2006, 04:49 AM

I took the cats out when I had my lt's installed and the car ran good for a few weeks, afterwards it started running rich and dumping lots of gas causing some of the plugs to foul up. I've heard of some people having probs with the sims, so I'm just gonna go with some hi-flo cats.

2000GTP · 12-07-2006, 06:35 PM

Quote:

Originally Posted by crushah

I took the cats out when I had my lt's installed and the car ran good for a few weeks, afterwards it started running rich and dumping lots of gas causing some of the plugs to foul up. I've heard of some people having probs with the sims, so I'm just gonna go with some hi-flo cats.

The rear 02 sensors have no affect on fuel management or engine performance, thus the 02 simulators will not have any affect on your engine performance and your plugs fouling up. Are you positive it is running rich and did you do a plug check? Long tubes with an off-road y-pipe is going to put off some smelly odors which will make you think your car is running excessively rich when it is not.