Will an EGR valve off a 91 350 TPI work for a 305? I'm having a hard time figuring this out. NAPA says there is two different models for my 91 Firebird 305 TPI, but they don't know the difference between the two. They say I need a certain number off the valve itself, which I obviously can't see with the plenum on, and I'd rather buy a used one anyhow. But I don't want to buy one made for a 350 and have it not work, since there seems to be a few different types out there.

Thanks for the help

 

Only way to know for sure is to take off the one you have. Some are labeled negative, some labeled positive, and I'm not sure there's a definite way to determine which engines had which one.