I would kinda doubt it. The exhaust- turbo mufflers probably did nothing in terms of reducing KR, as the cat back on most of these Wbodys is pretty good from the factory (particularly the factory dual exhaust), so its not a restriction.

The high flow cat is kinda in the same boat- a stock cat is pretty well matched to a stock engine, and isn't really a huge restriction. Plus, you're still running the exhaust through cat material- it would be slightly different if you had deleted the cat altogether- but I doubt this helped flow much at all.

The ubend delete helped for sure- and the resonator delete probably did a little bit (although the res on my gtp was pretty much straight through inside as it was). The cai/180/plugs will help a good bit, but I would honestly think without pcm tuning of some sort (even a canned pcm)- that you may just be getting to the point of 0 degrees of knock on the stock pulley (since most stock L67s have some knock).

As Lav said, its impossible to tell without scanning. After jumping to a 3.4 with similar mods on my gtp, and having the thing run stupid high knock levels (and having to unplug the bbv to cut boost until I got more mods)- I've changed away from the theory of more boost is better. I would rather have had the stock 3.8" pulley with full pcm timing (0* KR), than the extra couple pounds of boost with much less timing from all the KR.

Its different if you really truly are 100% knock free, and will be almost compeltely knock free on the new pulley- but if there is any knock now, or if you think there is a chance of it knocking with the new pulley- I would stick with stock for now.

 

yea I see what u are saying.
I'm not really trying to rush it honestly, just asking cuz I know a lot of Yall know about this.

though after I get my pcm flashed and the CAI and 180 spark plugs I do want to mod alot a little more after those mods.


I dont want to hurt my engine so I'm cautious

 

im also looking to mod my 04 s/cSS and i already have one of those aerometer scan guages from a previous vehicle... my question is will it work , it has a knock retard mode on it and i figure that reads throughthe obdII so kinda has to be accurate, but is this enough?

 

Yes, a scan tool gauge will work just fine. Its no more or less accurate than any other scan tool that reads through the obd port.