86 Pre Cats,Are they needed?
Thread Starter
Team Owner
Joined: Jan 2003
Posts: 20,324
Likes: 250
From: Summerland B.C. Canada
86 Pre Cats,Are they needed?
Out cruisin today and noticed rotten egg smell after some extended high rpm on the highway. The main cat is a year old,the pre cats unknown.I'm thinking these little buggers are congested and are overheating.Can i remove these and hope smell goes and more power returns? Thanks for any input!! :confused: :cheers:
Race Director
Joined: Aug 2000
Posts: 14,130
Likes: 7
Cruise-In II Veteran
Re: 86 Pre Cats,Are they needed? (AGENT 86)
I took off the pre cats and got the Y pipe without them and just use a main cat.I passed emissions in NY state where I used to live.You dont really need them,unless they need them to be there for Visual inspection where you live.
If youre getting a rotten egg smell,the cat is getting alot of fuel,and sometimes its the brand of gas.You may have an exhaust leak around the new main cat as well,so have that checked.Also find out if your motor is running a little on the rich side.
If youre getting a rotten egg smell,the cat is getting alot of fuel,and sometimes its the brand of gas.You may have an exhaust leak around the new main cat as well,so have that checked.Also find out if your motor is running a little on the rich side.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: 86 Pre Cats,Are they needed? (AGENT 86)
Replace the front Y & pre-cats with a 2 1/2" mandrel-bent SS front Y for a nice performance boost.
My setup still easily passes the smog-****'s sniffer.
My setup still easily passes the smog-****'s sniffer.
Melting Slicks
Joined: Jan 2002
Posts: 2,784
Likes: 3
From: Atlanta GA
Re: 86 Pre Cats,Are they needed? (65Z01)
Replace the front Y & pre-cats with a 2 1/2" mandrel-bent SS front Y for a nice performance boost.
My setup still easily passes the smog-****'s sniffer.
My setup still easily passes the smog-****'s sniffer.
Thread Starter
Team Owner
Joined: Jan 2003
Posts: 20,324
Likes: 250
From: Summerland B.C. Canada
Re: 86 Pre Cats,Are they needed? (65Z01)
That would be nice but a money is tight due to dog needing operation. Can i get them cut out and replaced with pipe. I have no smog check where i live. :cheers:
Le Mans Master
Joined: Jan 2002
Posts: 5,320
Likes: 4
From: Kyle TX (Because Mojo Made me fill it in)
Re: 86 Pre Cats,Are they needed? (AGENT 86)
Yes you can. I did that before I bought headers. However, if you do have visual inspections there, you will not pass because they can see the patch pipe where the cats used to be.
Team Owner
Joined: Sep 2001
Posts: 62,162
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Re: 86 Pre Cats,Are they needed? (AGENT 86)
You can pass the sniffer without them, as long as the main cat is good.
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