^^^ What he said. They can pull up all the emissions diagrams while they check.

I smogged mine last fall and the tech failed me the first time due to a vacuum line non-conformance. He was actually proud of himself that he found the fault and boasted that they just got re-trained on all the old car systems. What that entailed specifically, I dont know. But if you have a simple exhaust swap and all the other emissions stuff is there on the engine, just take a a few hours to swap the old exhaust system back on. Getting a new CARB compliant cat will help maintain the margin of safety of your emissions numbers too.

Pelican dannobe is a CA certified emissions test inspector and he regularly points out, in no uncertain terms, that you're not going to pull one over on anyone/ pass the visual test...

https://forums.pelicanparts.com/porsche-911-technical-forum/1070716-bitz-efi-ca.html

in Germany there's a exhaust specialist (Dieter Weiss) who created an exhaust for the 911 with the SSI heat exchangers and catalysts: https://www.dw-technik.de/produkte1/01_dw11fk32.php

I don't know the regulations in CA. But in Germany the year of first time registration defines the rules for the exhausts. You can probably lean the mixture a bit. The more exact the mixture, the less are the exhausts.
As well I can urgently recommend to make a fresh oil change right before the smog test. And before that I usually make a tour of at least 1 hour at higher speeds to burn free the exhaust and the engine.

Thomas

That won't work in California. We've done a lot of header/cat systems and have sport cats for the SC/Carrera. None of those are legal in California, only the CARB approved cat mounted to OE heat exchangers.

Since you just replace the exhaust system ..why don`t you just put the original on and go for the smog test after ..remove it....

Ivan

Based on all the above comments, I plan to install the old System back on the car.

Are old cars the only smog polluters in CA?
Why does CA stick it to the collector car hobby?
In NC if the auto is 35 years or older you are exempt from safety and emissions testing.

New cars can be polluters too, was driving behind a new M2 the other day and just from the smell you could tell that the owner had screwed with something. I actually started to feel a bit nauseous and parked it for a few, no doubt in my mind he’d fail smog.

I think the laws are pretty equal whether your car is new or old (since you just need to pass smog for your year/model), but those of us with old cars get the short end since parts are either NLA or expensive.

Would be great if we got a rolling 35 year exemption, or if your car is insured for <= 2,500 miles a year you’d be exempt. Why should a car have to pass smog if it’s hardly ever driven? Probably won’t ever happen though.

Cars 1975 and older are exempt from biennial smog checks in CA.

You can swap a newer engine into an older car, but I wouldn't do it without talking directly to the referee who will smog it. It's technically doable, but save money and any hassles by being proactive before you start. Talk directly to the referee.

It's not that CA doesn't like hotrodders, they just want the company modifying stuff to go through the proper channels. There are supercharger and turbo kits that are CA Smog legal.

There was a 30 year rolling exemption thing in CA. Gov Arnold shot it down.

Or ... if you want to keep the SSI exhaust architecture, ... add two cats – IF diy exhaust systems in the US are permitted even if smog tests will be passed.

https://www.dw-technik.de/produkte1/01_dw11fk32.jpg
Source: https://www.dw-technik.de/produkte1/01_dw11fk32.php

See post #24
This would only work in states that do not have a visual aspect in the smog checks. Systems that are not configured to use standard 911 mufflers create a different set of problems as well.

Uops, missed that.

FYI, if the company producing the parts wants to go through the process, they can get CARB approval. But this late in the game, the market for early 911 parts is likely so small that they'll never recover the R&D money.

In eastern North Carolina there is no emission testing for anything
A 2021 with the whole dash lit up passes fine.
As was already stated 35yr or older no safety or emission checks.
25yr or older no emission test.
35yr or older no nothing
I renew my reg. on line.

It feels like the whole world is moving to my beach town.

Another positive plus about owning a 35 year + auto in North Carolina is the property tax value can not exceed a five hundred dollar value.

In Nevada any car 20 years or older can go smog test exempt as long as you certify you drive it less than 5 k a year . As a side note they never check the mileage :)

They don't check the chip via electronics (no way to connect to it) and there is no way you can see the chip without taking the seat out/etc. That said I think OBD was required for 1996 model year and newer.

OBD began with the 993.