Want to replace the original system on my 81, very rusty and too quiet. I see Magnaflow  makes a complete bolt on with pipes, converter and mufflers. Does the air, smog pipe reconnect as well? Looking for more sound and would like to keep motor stock otherwise. Thanks! 

Not sure on that one.  I purchased a bolt on replacement "free flowing" cat years ago.  Got a little more rumble without messing with the original system.  I had to buy some heat resistant gray converter tubing $$ to complete the hookup.

Will it pass State Inspection without the Cat? If so, Just put a regular performance system on and enjoy it. 

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Assuming you are keeping the original exhaust manifolds and an OEM equivalent converter, then all the emissions stuff should hook right back up.

If your state does not require a converter then I would go with the factory side exhaust as it's an easy way to do it plus it has very nice sound.

1973 L-82 4 spd

So, if I don’t go with converter /stock setup what happens to the air pump smog pipe that would go to the converter? Would my computer know the difference 

I've been told if a converter is removed from the exhaust system the air pump and its associated pumping can go away.  I can't say for sure but would think the computer would need to be reprogrammed to not look for input from the O2 sensor(s). 

Jim Olson 

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