The engine light only flickers sometimes when it is acting up when the boost kicks in at those speeds. So knock retard is this violent shuddering/jerking and such when the supercharger kicks in? And it is because of the plugs and/or the pulley being smaller? So now I need a scanner to set kr to 0? Then I get a downpipe and hi flo cat? I was not aware that I had to have it checked for kr before anything was done. How much is that going to cost me? Before ANY mods were done we took it to the track bone stock about a month or so ago and it did 14.95 1/4 mile. We wanted to compare before to after the mods. This is my daily driver. Didn't want to go too crazy with it. Later we will check the plugs again and try to get the 3.4 off. Hope I didn't break anything.

 

Read the thread in depth that I posted. It will tell you how to safely mod your L67 towards the goals you want.

Use it only as a guide though, not a tell-all list, since every car varies

*EDIT*

Here's a good read about KR

http://www.zzperformance.com/grand_p...les1.php?id=20

 

And then I should get 104's instead of 605's with the 3.4, downpipe and hi flo cat? Please pardon my ignorance. Anyone in NJ that I can take it to for this kr 0 scan etc???

 

We are going to take off the 3.4 and put the 3.8 back on. We are going to leave the 605 plugs in because the old 606 are already gone in the garbage. I can't afford having to get a downpipe, headers, hi flo cat, rockers, getting KR tuned to 0 then getting the pcm tuned again for the other mods, etc., just so I can put that pulley on. Looks like I will be selling the pulley puller and the 3.4 pulley. Damn puller alone cost me around 150 with shipping plus the cost of the pulley! Thank you for everyones help.

 

In the future when you want to change a pulley, you can rent the pulley remover tool from vendors, like ZZP. Then you don't have to waste all that money if you aren't going to change pulley's frequently.

 

Another great idea is the modular pulley systems, that way you only need to tool once and can change pulleys easily with mods.

Like everyone said, I think scanning is all important. Its not always convenient to have the PCM tuned right (I have to travel to another city where I know somebody), but you know it will work and optimize whatever you have set up. A "canned tune" can't do that for you.

You have a cat back. Has the u-bend been deleted? This might help KR a bit - cheaply

 

I plan to get a u-bend delete downpipe with hi flo cat, but in meantime am taking off 3.4 and putting 3.8 back on till I can get my car scanned for KR. Also hearing that supercharger oil needs to be changed from some of you but varying from every 8,000 miles to every 30,000 miles. They sell a kit on ebay with the oil, etc. Oh yeah, the problem with it breaking up was a bad wire. It got damaged when the 605 plugs got put in. Runs excellent now but still taking off 3.4 to be safe for now till I get a reading and a downpipe, or just keep it off alltogether....thank you everyone...

 

I'll chime in here:

It's WAY too soon to put on a 3.4 pulley.

At best, you are probably only ready for a 3.6 pulley.

Too go down to a 3.4 requires more than what you have already done for mods.

 

You don't need to buy a kit on ebay to change your supercharger oil.

You just need to go to the dollar store and get something like a soap dispenser, or spray bottle that's empty. You stick the hose into the supercharger snout (there's an allen hex bolt that you unscrew) and squirt / pump the old oil into the bottle that you purchased.

Then you fill it back up with GM Supercharger oil (ONLY GM supercharger oil, you can pick up 2 bottles at your dealership, or ZZP sells them) You need 6 oz. So you would have to buy 2 4oz bottles, or ZZP sells a 6oz bottle

 

Thanks Chibi! And what is your opinion on how often to change it?