Knock....Knock - Boost Forum

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Knock....Knock
Tuesday, August 28, 2012 5:35 PM
Im fairly concerned about the amount of knock im getting on my supercharged cav.

I run 94 octane fuel only, have one step colder ngk's with whatever gap they come with, intercooled, LSJ header and 2.5" downpipe and cat.

Im still getting the same knock after doing all that as I was before. So its not heat or a bad cat.


But it seems first and second gear aren't to bad but anything after that the interceptor says im getting knock. The highest it ever gets to is 7.9* of retard. Which cant be good.

Is it just a reflash thing, or should I be looking to regap my plugs down to say .035? Or could it be related to my non existent pcv setup?

Re: Knock....Knock
Tuesday, August 28, 2012 6:04 PM
What plug are u using?



Re: Knock....Knock
Tuesday, August 28, 2012 7:02 PM
plugs? gap?

AFR's?



FU Tuning



Re: Knock....Knock
Tuesday, August 28, 2012 7:47 PM
He already said he's running the 1 step colder NGK's

I'm assuming they are the LTR6Ix-11's / NGK#6509
They come with a .040 gap.

Try gaping them down to .030, my 2 cents.



I roll on steelies. Work-in-progress daily-sleeper potential.
http://www.j-body.org/classifieds/engine/60493/
Re: Knock....Knock
Tuesday, August 28, 2012 8:45 PM
Your correct....^^^^

Those are the plugs and gap.

As for afr I dont know as I havent bothered to put my wideband in yet. Im on the reflash so id imagine im pretty rich. Ill do a couple pulls tommorow and see what kind of timing its timing for at wot.
Re: Knock....Knock
Wednesday, August 29, 2012 4:11 AM
Philly D wrote:

Your correct....^^^^

Those are the plugs and gap.

As for afr I dont know as I havent bothered to put my wideband in yet. Im on the reflash so id imagine im pretty rich. Ill do a couple pulls tommorow and see what kind of timing its timing for at wot.


You posting about knock, yet you do not have a wideband on the car. Until you put the wideband on stop posting about it.



FU Tuning



Re: Knock....Knock
Wednesday, August 29, 2012 4:21 AM
Addicted to meth wrote:

Philly D wrote:

Your correct....^^^^

Those are the plugs and gap.

As for afr I dont know as I havent bothered to put my wideband in yet. Im on the reflash so id imagine im pretty rich. Ill do a couple pulls tommorow and see what kind of timing its timing for at wot.


You posting about knock, yet you do not have a wideband on the car. Until you put the wideband on stop posting about it.


Righty - oh....ill post when I get it hooked up.

No need to be brash though. If I knew I needed my wideband in before posting I would have done it first. Now I know and ill post my readings after.
Re: Knock....Knock
Wednesday, August 29, 2012 6:14 AM
... who's there?

hi, im the #3 rod bearing.



I choose the technology built for land speed records... not the technology built to save on emissions and gas mileage.
Re: Knock....Knock
Wednesday, August 29, 2012 6:31 AM
I hope you are not gapping those down that far, when the gap exceeds 0.008" modification of the out of the box gap we tend to see weakening of the ground strap weld to the base of the plug.


Oh and BTW this plug comes out at 0.044" thus the -11 at the end 1.1mm=0.044"


Agreed with the wideband.



Re: Knock....Knock
Wednesday, August 29, 2012 7:31 AM
I'm still getting a random rich condition every once in a while, but I have no knock to speak of and I'm not even running a h/e on the crapflash.
Re: Knock....Knock
Wednesday, August 29, 2012 7:38 AM
Quote:

I hope you are not gapping those down that far, when the gap exceeds 0.008" modification of the out of the box gap we tend to see weakening of the ground strap weld to the base of the plug.



This is why I recommend the 3787's.



FU Tuning




Re: Knock....Knock
Wednesday, August 29, 2012 4:58 PM
I havent gapped anything as of yet...going to get my wideband hooked up makeshift for now to see whats going on. Then ill post back what im seeing, and work on plug selection, gaps etc.

These the plugs we should use for my application?

http://www.summitracing.com/parts/ngk-3787/
Re: Knock....Knock
Wednesday, August 29, 2012 6:19 PM
Addicted to meth wrote:

Quote:

I hope you are not gapping those down that far, when the gap exceeds 0.008" modification of the out of the box gap we tend to see weakening of the ground strap weld to the base of the plug.



This is why I recommend the 3787's.



these are what i just put in my car!!! car seems so so so much smoother and happier under boost now. they are gapped at .032 straight outta the box.

As for knock and the reflash, I have been told by a few very very smart and knowledgable peeps, one being a GM calibration engineer, that it pulls 'around' 8* of KR no matter what if it sees any knock. so you might not actually be getting that much knock. I have the torque app, and it jump straight to 8, then comes back to zero. its built in safekeeping really.

What pulley are you on? I am on the 3.0.

I havent really had a chance to check since i put the 3787's in since my heat exchanger pump is bad right now, but with STOCK plug i would get 8* of KR in 3rd and 4th at WOT. i could pedal it all the way to redline, or the fuel cut off in any gear and not have any knock. I also know that when I have this "knock" i am i n the 11.2-11.7 range AFR wise, so i know i have enough fuel. its a timing thing. or a phantom thing IMO.


Here is where I just got mine from. 41 and some change shipped to my door Its the cheapest I found them.


Edited 1 time(s). Last edited Wednesday, August 29, 2012 6:22 PM


Re: Knock....Knock
Wednesday, August 29, 2012 6:31 PM
Thanks Evo...

Maybe thats what Im seeing if it comands 8* if it sences any knock.

Im on the stock pulley currently. I may grab those plugs just cause its been a year and its prolly time to change them since I drive alot. That being said mine doesnt really come back down to 0..itll come down after the initial spike..

Gotta find me a makeshift pod to get my wideband in.
Re: Knock....Knock
Wednesday, August 29, 2012 6:49 PM
it shouldnt come right back to zero. it will return half a degree of timing every .5-1 second. atleast that is what mine does. yeah and i have not seen any more the 8* EVER, even without the heat exchanger.

it did the same thing to me on the stock pulley. and the way i look at it, if i get 8* on the stock pulley, i should get more on the 3.0 pulley. But i dont, so IMO its not that big of a deal. I read and read and read about knock and KR when i put my 3.0 on, and everywhere I have read (except here) says that if your computer/car takes advantage of KR (meaning does something to get rid of the knock) then seeing anything below 10* isnt to be worried about unless it stays and doesnt go away. meaning if the knock isnt going away, then there might be a problem. but mine will jump to 8*, and 6-7 seconds later be back down to 0 with my foot still in it.



Re: Knock....Knock
Wednesday, August 29, 2012 6:52 PM
Main point, any time you ever put a power adder on, step 1 should be a wideband. even before you put an SC on, wideband.


Re: Knock....Knock
Wednesday, August 29, 2012 8:22 PM
^^I bought the car with it already on

Ironing out the issues. As I go! I got the wideband but was waiting for my downpipe to be made so I can install it.
Re: Knock....Knock
Wednesday, August 29, 2012 11:13 PM
jason norwood wrote:

I hope you are not gapping those down that far, when the gap exceeds 0.008" modification of the out of the box gap we tend to see weakening of the ground strap weld to the base of the plug.


Oh and BTW this plug comes out at 0.044" thus the -11 at the end 1.1mm=0.044"


Agreed with the wideband.


Gapped mine to .032 -- I'll let you know when the plug falls apart.



I roll on steelies. Work-in-progress daily-sleeper potential.
http://www.j-body.org/classifieds/engine/60493/
Re: Knock....Knock
Thursday, August 30, 2012 5:11 AM
^^He works for NGK I believe so he may have a clue what he is talking about when it comes to plugs
Re: Knock....Knock
Thursday, August 30, 2012 5:56 PM
EvoFire wrote:

As for knock and the reflash, I have been told by a few very very smart and knowledgable peeps, one being a GM calibration engineer, that it pulls 'around' 8* of KR no matter what if it sees any knock. so you might not actually be getting that much knock. I have the torque app, and it jump straight to 8, then comes back to zero. its built in safekeeping really.


Must not be THAT knowledgeable because they are WRONG





ASE Master Certified Automotive Technician

Re: Knock....Knock
Thursday, August 30, 2012 6:42 PM
Eric Knight wrote:

jason norwood wrote:

I hope you are not gapping those down that far, when the gap exceeds 0.008" modification of the out of the box gap we tend to see weakening of the ground strap weld to the base of the plug.


Oh and BTW this plug comes out at 0.044" thus the -11 at the end 1.1mm=0.044"


Agreed with the wideband.


Gapped mine to .032 -- I'll let you know when the plug falls apart.


He is right. It is not soo much about the plug falling about, as it is the grounding strap breaking, not really making the right connection. We have ran across this and the car would run like it had a fouled plug.

With the 3787's pre gapped at .032and works. They are more pricey, but makes things more simple.



FU Tuning




Re: Knock....Knock
Thursday, August 30, 2012 10:10 PM
CaliforniaDomestics wrote:

EvoFire wrote:

As for knock and the reflash, I have been told by a few very very smart and knowledgable peeps, one being a GM calibration engineer, that it pulls 'around' 8* of KR no matter what if it sees any knock. so you might not actually be getting that much knock. I have the torque app, and it jump straight to 8, then comes back to zero. its built in safekeeping really.


Must not be THAT knowledgeable because they are WRONG


maybe!



Re: Knock....Knock
Monday, September 17, 2012 9:12 AM
Well would anyone believe a new belt seems to have made it knock alot less?!

I blew my belt yesterday and humped it home with the surviving 2 ribs.


Changed the belt and now my interceptor is saying I'm getting less knock
Re: Knock....Knock
Monday, September 17, 2012 9:16 AM
Ill add to this. I am getting zero to 4 on my knock. Versus almost instant peg to 7.9.

I hit 7 once this morn when I pinned it on a off ramp but in 3rd it only went to 4.

Odd
Re: Knock....Knock
Monday, September 17, 2012 9:33 AM
I could see this in a tensioner possibly, or if the belt is bouncing around... causing the shoe in the tensioner to rattle against the engine...



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