Side Exhaust
Safety Car
Joined: Jun 2004
Posts: 4,652
Likes: 80
From: Lakeland Florida
Maybe a gray area. Because the 1975 is smog exempt, it only means it does not have to go through the smog check. But it is illegal to tamper with or remove emission controls on the vehicle. The 1975 came with a catalytic converter, so removing this to put on the sidepipes would make it illegal.
From the EPA website
http://www.epa.gov/
EPA’s prohibitions against tampering and defeat devices apply to certified products throughout the United States, including products that are certified to meet emission standards that apply uniquely in California.
kdf
From the EPA website
http://www.epa.gov/
EPA’s prohibitions against tampering and defeat devices apply to certified products throughout the United States, including products that are certified to meet emission standards that apply uniquely in California.
kdf
Melting Slicks
Joined: Jun 2003
Posts: 2,802
Likes: 241
From: Niles, MI
When i moved to CA 4 years ago, I had to get my 73 inspected by the CHP to get it registered. It had side pipes at the time and smog air pump removed. Never said a peep about anything. 75 may be different though.
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,557
Likes: 7,006
From: New Or-leens Loo-z-anna
If necessary, install a 3.0 liter "mini-cat" directly below EACH exhaust manifold (of course stock exhaust manifolds or "shorty-headers would be a necessity)...the run a 3" exhaust pipe from each cat to each sidepipe.
Driver=Happy...................CHP=Happy .............Win/Win
Driver=Happy...................CHP=Happy .............Win/Win
Le Mans Master
Joined: Feb 2011
Posts: 5,943
Likes: 61
From: Southern NH
yup, California requires what was on the vehicle from the factory to pass. So it has to be a y pipe into a single cat and then a y pipe out to two mufflers. You cant do two single pipes with a Cat in each one, it will fail. This sidepipes will fail. with or with out cats.
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,557
Likes: 7,006
From: New Or-leens Loo-z-anna
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,557
Likes: 7,006
From: New Or-leens Loo-z-anna
Drifting
Joined: Jan 2014
Posts: 1,866
Likes: 140
From: Sadieville Kentucky
Smog check VS CHP check
Having owned a 75 for 20 years and a smog station for 40 years here is my go on this . first of all CHP is not a smog person they only verify Vin #s .The reason people look for 75 and earlier models it because they can get their car licensed with out haven to have smog issues and can run with what is on their car .yes it is not legal to remove smog equipment (just ask Mr motion Joel Rosen ) what happened, no one is going to throw you in jail for driving around with side pipes on a 75 .There are some good things about being in Ca.
Thread Starter
Racer
Joined: Aug 2007
Posts: 270
Likes: 1
From: So CaL
Having owned a 75 for 20 years and a smog station for 40 years here is my go on this . first of all CHP is not a smog person they only verify Vin #s .The reason people look for 75 and earlier models it because they can get their car licensed with out haven to have smog issues and can run with what is on their car .yes it is not legal to remove smog equipment (just ask Mr motion Joel Rosen ) what happened, no one is going to throw you in jail for driving around with side pipes on a 75 .There are some good things about being in Ca.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
Your later answer infers that you have a 1975, which came with a catalytic converter.
Which is it?