Can anyone explain this "noise reduction" California law?

[Dibbons]

I see California vehicles (71-72?) could not be ordered with factory exhaust trumpets (tailpipes must be turned down). Two questions: a) Where can I find the written law/regulation that prohibits this option? b) Is there really any difference in sound between the regular tail pipes and the trumpets? Thank you.

 

[GetX'd]

I would call a CA Sheriffs office to inquire. I've never heard of the law. Is it only for those years or is it those years and newer?

 

[jimt1971rr]

Being that this was a "law" back in 71/72, I doubt that you will find anything. One thing to remember is that the California government are a bunch of stooges and have been forever. In case you don't remember, or weren't around then, in the later 70s you couldn't buy a car in California with a V8 and a manual transmission. Even the Trans am's of the late seventies were ALL automatics if sold in California. Again, I don't think you could find a law or regulation to this fact nowadays, but it was true. It wasn't until the 5.0 Mustang came out in 1982 that you could get a manual transmission again. This was more for smog than noise but still!

 

[Dibbons]

I am sure it is not a "law" as in penal code or vehicle code, but some kind or rule or regulation back then (maybe connected to California smog requirements). All i know for sure ,is my parents new (special order) 1971 Road Runner had turned down tailpipes and if you examine archival optional equipment brochures/guides you will see notes that the optional exhaust trumpets are "not available in California".

 

[flypaper]

a little history is involved

back in 1970 congress passed the clean air act
it was made specifically to reduce smog and air quailty in l.a. california
back then the smog in california became a big concern.
califorina was the biggest supporter behind this act.
it gave car companies 5 years to reduce tailpipe emissions by 90% by 1975
califorina even took it a step further and made even further regulations
trying to speed up that 5 year timeline
that is why california cars 1970 and later usually have extra pollution controls on them
or they disallowed certian exhaust related things such as the trumpets.
or even manual transmission cars later on as someone mentioned.
i think in 1990 the act was updated further.
it is also the reason why the muscle car era ended in the 70's
tail pipe emission concerns choked out horsepower.
it took decades for the car companies to overcome this
and make cars like they are today.
if you want further information i think california has a detailed
web site dedicated to the subject covering all
of thier past and present clean air/enviroment regulations.
i'm sure its a very long read..lol

 

[Dibbons]

It's pretty universal that a manual transmission gets better gas mileage than an automatic, at least until more recently. I don't see the point in California limited a standard transmission (long haulers have a standard transmission and for good reason). Anyway, if "lawmakers" were responsible for the disappearance of them, I think that was stupid.

 

[jimt1971rr]

I could be wrong about this, but I think the main reason had to do more with the timing of the engine of an automatic vs a manual. Remember, that just because an engine uses less fuel, doesn't mean that it produces less emissions. For example, motorcycles with out any sort of smog equipment produce a lot of emissions compared to a modern V8 car but still gets considerably better gas mileage. I agree it was stupid, but at the time, it was the only way the automakers were able to meet these regulations. Thank God those days are over!