E30 M3 Engine Swap in California?


Full member
USA - Fresno
2001 Saturn L300
Hello! I have a few questions here but before I just drone them out ill explain myself. I will be soon starting a new job with more money to save! I want to do a tuner car but at the same time I don't want to waste cash and insurance dollars on speeding tickets haha!

I know it's a big project and probably very costly, but before I even look at that stuff I need to know if it is even California legal. Thanks to all of our state laws, cars aren't very fun! So I'm to the point where I would like to have a nice solid oldie with a new heart in her! Probably a sound system too :p

So any information you can provide would be great. I've looked at laws and such about engine swaps and it seems legal to swap out an engine of the same class (for example light sedan engine with another sedan engine but not truck to sedan) but then they talk about smog and not touching the catylitic converter.

Any idea? ANY HOPE!? Let me know, thanks.

(I want to do an s50 swap)
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Staff member
2011 Honda FN2
May I suggest you search the current modification regulations in your state/county to see if it is possible to be done legally .
FWIW over here we can install a later model motor in an old car BUT it must have the cat fitted IF one was fitted in the car the motor came out of. We also have private engineers who are alowed to check and pass certain mods and issue compliance certificates.In my case I have "blue plates" in the engine bay listing the approved mods so if pulled up by police or transport inspectors they can see that my mods have been approved.

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