...I am knocking like a bi**h!!!

First off I can notice a BIG difference with the 3.4 and supporting mods. But we could not figure out why it is knocking so much. I'm getting like 2-4* sometimes 5* of knock as soon as I hit 65% trottle.

We think it could either be fuel or exhaust related. He asked what kind of fuel I run and I said the highest octance. So he told me to try a different brand and we also put some fuel injector cleaner in there. So we'll see how that goes later on it the week. Also thinking fuel injectors. Other thing he was talking about was exhaust. He was think at some point I should end up going 3" the whole way back cause it gets kinda restrictive toward the cat.

Another thing he metioned was something concerning the dampener and chain, I believe, but don't hold that to me.

So we are really puzzled, so any suggestions will more and likely be looked into. Thanks guys!

Mod list?

The pulley is too small.

What supporting mods?

2-4 sounds like normal with minimal supporting mods.

Here you are guys:

2000* Ceramic Coated Pacesetter Headers/3" Cat'd Downpipe, ZZP 3.4 MPS, Gatorback Belts, GMPP Sway Bars and Trailing Arms P/U Endlinks, K&N CAI, Optima Battery (Red-Top), Autolite 104's, PRJ 10.4mm Race Wires (Red), Drilled 180* T-Stat, ZZP 3-gauge Pillar Pod, Aeroforce Scan Gauge (Red/Black), Glowshift Oil Pressure and Boost Gauges, ZZP S/C Coupler, Drilled/Slotted Zinc Coated R1 Concept Rotors, Hawk Ceramic Pads, ZZP High FLow Fuel Filter, Aluminum LIM Gaskets, VVME 8000K HID's

no pcm upgrade or tune?

Yes Tuned by PRJ Performance, sorry

So.... Headers, intake, T-Stat, and tune.

Looks like you have one of the lucky cars that needs more. Or get a bigger pulley.

YES!!! I'm so excited to spend more money... SIKE!

Yeah, I guess that's the price you get for modding right...

Someone was telling me to look into a wideband. So what else to you think I should add to the list to get rid of some KR. I've also heard fuel pump and/or injectors and a cat-back to replace the stock piping.

Did you flip your sway bar? It could be false knock.

Some people have had to stratigically place dynomat in the engine compartment and it solved some of the strange KR.

Actually someone else mentioned that on another board. Said it could be rubbing on the headers.

Sway bar on the downpipe can cause false KR. Take off the S/C belt and go WOT. Do you still get knock?


A wideband is absolutely needed. It is a shot in the dark without one. You don't need injectors yet, I would guess your fuel filter before your fuel pump.

Only way exhaust could be the problem would be if you had a clogged cat. How agressively did PRJ tune? You may just need to decrease timing for the smaller pulley.

you got the Aeroforce, let us know some things.

LTFT's are important when you go WOT as well.

If your LTFT's when going WOT (or over like 50% throttle) are NEGATIVE, then that is not very good, neither is being positive but atleast you won't blow the motor from leaning out.

Your PCM has a base value in it for fuel trims when it goes WOT. This base value then adds or subtracts your LTFT from it when you go WOT. So if you're LTFT is negative when you start accelerating and then you go WOT it will take away X amount (X = LTFT) from that base value in your PCM. That could be causing your knock as well, it could be either too rich or too lean. A wideband would be able to tell you exactly but since you don't have one we'll have to work with your LTFT's.

When at WOT or whenever you are seeing knock what are your:

LTFT's
MAF freq
Ignition Advance (timing)
KR
Injector Pusle width

actually, you want your LTFTs to be slightly negative, never positive. If they are positive, you are running lean, PCM has to add fuel to correct the condition.

yes, you are right, but I said when going WOT. When going WOT, it's a completely different story. Some sensors are ignored and other values are put in place.

When cruising around, you can be a little lean and not really worry, their isn't much load on the motor.

If the LTFT's are positive it means that it is adding more fuel to the mixture (yes, you are right, it's running a bit lean) BUT it's doing so to make it stoich. So when it is stoich it is neither rich nor lean.

So, when going WOT if it is negative (taking away fuel from the mixture) it's taking away fuel from the base value which is a best guess stoich mixture, which in turn may very well lean it out. Like I mentioned before, going WOT is a completely different story than just crusing and you'll never know if you are rich or lean at WOT without a wideband.