hey, i just recently bought a 2004 monte SS supercharged i want to put th 3.4" pulley on, but i've heard so many things i shold do before i do this, such as transmission cooler, cat back exhaust (which i have no idea what that is), and fuel injectors. can anyone help me clear this up and give me the best information to have the best performing car

 

EASY! First, the factory cat-back exhaust is good to over 400hp, so changing it is for personal taste. There's a few things you NEED to do, and things you SHOULD do.
MUST DO's: 180d t'stat, colder plugs, either Autolite 103 or 104's or NGK Iridium TR6's, a GOOD cold air intake, such as a K&N or Wizaired, and a U-bend delete pipe. You will need a different PCM to let the engine know that you are running a 3.4". GOOD GAS!
Other helps: PLOG front exhaust manifold or TOG or SLP headers. Stay away from the pacesetters as you will lose torque. Ceramic crossover and ported rear manifold, larger throttle body, 1.9 rockers or a small cam, but NOT both. You want to start to tap into it's potential: add an intercooler! Some here are running 3.1" pulleys, and the MIGPClub guys here in MI are running smaller than that!
Several of us have broken our flex plates, so BEWARE! If you hear a sound like a fan blade rattling, pop your inspection cover and check it out. I broke 2. 1st had crack going from the center out, and the 2nd had breaks at the bottom of the windows, as I twisted the center out of it. Hoping the 2500 stall convertor at 8 lbs lighter will cure that problem for me. I'm only running a 3.4" pulley!
Good luck!

 

Pretty much on the money. NEED TO GET A SCANNER/TUNER AWAY!!!

Forget the tranny cooler unless you are going to be towing.

 

Thats what we told him in his other identical thread:

https://montecarloforum.com/m_93549/..._/tm.htm#93549