Yeah the thing is I dont really want to get too deep into scanning and modding for ALOT of different reasons. Money, time, and the fact that I need my car to survive as it is my daily driver.

What I wanted to do was lower the pulley slightly without doing any engine mods, give it a good tune, and monitor the engine with my aeroforce. Give it a one and done sort of deal just to get a little bit more power.

If I cant kill some KR I may just keep the stock pulley on and tune it.

Not all cars run the same, but a general rule of thumb is you should be safe to drop down to a 3.5 pulley with CAI, 180* Thermostat, colder plugs (1 range colder is enough), and a good tune assuming you can run 93 octane fuel. Any lower octane and you are increasing your chance of pre-detonation.

Something else I would personally recommend if you plan to stay mild is the rocker upgrade. I've got modified 1.9 ratio rockers, the true 1.9:1 roller rockers are the best way to go. Either way, paired with the smaller pulley it gives you a very noticeable HP increase with minimal impact to cruising MPG.

Take a look here if you haven't already: https://www.gmforum.com/performance-...engine-278662/

I had planned on adding a 3.6 inch pulley, copper plugs (one heat range colder), and a 180* thermostat to my setup. I had always heard that a 3.5 was with a few mods, so I figured that I could get away with a 3.6 with what I got plus a good tune.

How much would rockers help?

did you get gas from a different station, i would try like hess some stations have bad gas

1.9:1 Rockers would add a conservative 20HP at the crank. It allows you to take better advantage of the added boost from the smaller pulley, and the smaller you go the bigger the difference it will make to a certain extent.

It'* possible, but I usually fill up at Mobil.

I forgot to mention that ive been battling a P0420 code too. I don't know what effect that would have on my KR problem but I will be fixing it along with a few new parts. Here is a list of what is goin in this weekend, we'll see if it helps tame some of that KR...

-spark plugs, Autolite 605'*, one degree colder than stock.
-spark wires form AC Delco
-O2 sensor
-180* t stat