I am shopping for a Y-pipe. After looking through lots threads I saw a mention that the 99's need headers to see gains from the Y-pipe due to more complicated emissions.

Is this true? If so, what exactly is different? Will the typical header/y-pipe combo fit without issues?

 

The '99 Cali specs have a precat bolted on to the front exhaust manifold, same as the 2000 Cali and 2001 and up.

Yes, headers and Y will be fine. Search 'fed spec conversion', you can just install a Fed spec front manifold and use a regular Y.

 

Ok cool, since mine isnt a cali spec I guess I dont have anything to worry about. I just saw something about it in one of the threads and it made me a bit worried. Guess I will go order my y-pipe now

 

Check to make sure you are not cali spec. I live in michigan and had a cali spec 99 so the area you live in means nothing.

 

How can I tell which is which? I bought it brand new from the dealer in Arkansas so I hope it isnt a cali spec!

 

cali spec cars were not only sent to california, my car came from texas originally and it was cali spec

look on the front of the motor, how many plugs are on the coolant runner behind the fans?

 

Two plugs on the coolant runner.

And while we are on the subject. All of the catbacks I am looking at say I will need an extra sensor pipe and they offer to sell me one for $45. Whats up with that?