I've searched the forum for answers but unable to find it. The folks in CA I have a 78 SC that needs new heat exchangers. I would like to install SSI or headers on my car. I'm located in the Midwest at the moment but anticipating of moving back to SoCAL soon. Can I pass SMOG inspections?

 

SSIs or headers have no provision for the use of a catalytic converter so you would fail the visual but might be able to pass the tailpipe. I do know of people who have built a custom cat that fits where the muffler usually does in order to pass smog.

 

SSI's are not legal in CA for a 78 according to the letter of the law. There are many smog check stations that won't know what the correct stock setup is for your car so there is a chance you could pass the visual inspection. I doubt the car would pass emissions without a cat though. I have seen SSI's used with a custom exhaust that utilized a very small cat on each side between the heat exchanger/header outlet and the muffler inlet. The owner claimed that it passed CA smog on his 87 Carrera. But just FYI, CA smog is a real hassle!! If you want to mod the exhaust I would suggest keeping the stock system for smog and bolt on the system you want between biannual smog checks.

 

You can switch but you have to change out those oil lines too, definitely a PITA.

 

Unfortunately the stocks are rusted out. That's the reason for replacement. What are the rules if I register as antique? Do you know HP gain with this setup?

 

Hi,

"TT Oversteer" offered excellent advice; you'll not pass smog without the stock exhaust unless you live somewhere they do not test those cars. Only pre-'76 cars are exempt from smog testing and inspection. Many people here do this bi-annual swap between the stock and a SSI system to enjoy the performance gains.

You can always buy a used pair of HE's for this purpose so thats not a big deal.

SSI's and a good dual-inlet Sport muffler are worth around 20-22 BHP so its well worthwhile if you are looking for more performance (something difficult to do on these CIS cars).