I was told that since I'm putting in an older 350 into my 87 camaro, that I wouldn't need a cat due to the age of the engine. Is that true?

 

depends on the state. in pa, if your car came with a cat from the factory, you must retain one. you could put a model t engine in an 07 vette and still need a cat, egr, whatever else...

 

I currently reside in Michigan. Anyone know for this state?

 

Most states go by the emission sticker under the hood. If it says catalyst then it needs one, but if the engine is a 1974 or older then you might need to document that it was a swap and prove it, to be legal. I was told that, when I lived in Atlanta. Cobb county has emissions testing and I had a 80 Olds I converted from diesel to 76 olds gas motor and they wanted me to pass 76 standards but the sticker under the hood said non-catalyst so emission testing was not required. In my experience there are repair shops that will not work on exhaust without a cat if the car originally required one whether the motor is pre 75 on not.

Best thing to do is ask the state EPA

 

You could probably easily find out by checking out your state's DMV website.

http://www.dmv.org/mi-michigan/smog-check.php

I found that don't know how true it is though...

 

do you have to have emissions test. If so put it back if not lose it

 

Federal law states that the emissions requirements are for whatever is newer, and the engine cannot be older than the chassis for emissions requirements.

Basically, what you were told (in the original post) is absolutely, positively wrong - regardless of the state. A shop can be severely fined for removing emissions equipment, regardless of the state in which it may be located. It is typically federal sting operations that get them in trouble.

Enforcement, of course, is entirely a different matter. Privately owned vehicle emissions inspections and/or testing is basically left up to the individual state or region, based on their compliance with overall air quality as determined by the Federal EPA. Therefore, lightly populated areas, or areas with good natural "cleansing" winds, won't have to impose inspections/testing on their populaces. More densely populated area, and those where atmospheric conditions don't lend themselves to natural "purging" (like LA), will have more strict inspection/testing requirements.