i have a 85' T/A with a 305 4bbrl LG4... the car is otherwise stock execpt for a flowmaster, i was wondering if the flowmaster will cause my car to not pass smog... i live in california so emissions standards are a bitch here.... i would rather keep the muffler on right now so is there anything i can do to lean up the car's emissions other than a basic tune-up.... i think she's running really rich right now so how do i tune the carb down for the smog pass?? and should i change the o2 sensors or does that not make a difference on the emissions, thanks....

 

Living in NJ we have tough standards too. The muffler, so long as it doesn't have a hole in it, should not cause a car to fail emissions since they're testing for things like Nox and so on. The chamber design on your muffler will make the car sound better, but it doesn't change how the engine is running. I would say make sure you have no more than 91 octane in the car, and make sure the thing is warm by the time they go to stick the sniffer in. If the car is cold, and I failed because of this once, the engine is not burning properly to have the right emissions GM so wisely decided could only be achieved by running these engines over 200*. Just make sure the car is warm, and you should pass emissions, everything else is another matter though!

 

hehe, hail small town atmosphere, no emissions in my county, lol. Good luck passing your inspection

 

You should pass since the guts of the engine is stock. If you have not replaced your O2 sensor in the last 50k miles, be sure to do that before taking the thing in for the test. And drive it around for a good half hour before taking it in to make sure the engine and cat are HOT.

I also live in Cali and my IROC passes, but only if the engine and cat are toasty. I have a Magnaflow muffler.