Knock Retard while cruising. What am I doing wrong?

[Deutschezl1]

So i have read several threads about people seeing knock while cruising even while stock. I just installed a rotofab and a 10% pulley so far thats it. To start tuning i pulled 4° of timing across the entire HO table and im still seeing as much as 6 KR while cruising. I have an aem wideband installed so i know im not running lean. Before i started tuning i installed fresh ngk tr6ix gapped at .035. The stock acdelco plugs in the front two cylinder were toast. I thought the new plugs might solve the issue but im still seeing the same knock as before. So my main question is this. Is the factory HO spark table that aggressive in low load areas that i need to pull more timing down low? Im seeing what looks like burst knock just short spike while shifting and cruising sometimes during quick throttle changes, but what i am worried about is once or twice a log where i see knock jump up to 4-6° and then slowly trail off. Do i need to pull more timing down low or is low throttle knock not as dangerous as WOT KR? What to get this resolved soon. Still very new to tuning. I have watched just about every goat rope garage video i can find on tuning these cars. It has been super helpful to the point im considering jumping on his patreon so i can discuss tuning files one on one with him. I will post a screen grab from my logs later when i get off work.

Any and all help is very appreciated.

[chevy pilot]

I have also 4-6°,no worries.

[RobZL1]

I'd start by looking to see if an exhaust pipe is hitting the frame, or if some other mechanical contact exists. If you have already pulled 4 degrees from the HO table and you get any knock retard while just cruising around steady state, it is not real knock. Find the source and fix it, otherwise you'll build this great HO table that never gets used because your knock learn factor will always have you somewhere between HO and LO tables.

On my car, I don't get any knock, other than a 0.1-0.5 degree blip occasionally on takeoff from a dead stop. I have never seen any knock while cruising.

[Deutschezl1]

Originally Posted by RobZL1

I'd start by looking to see if an exhaust pipe is hitting the frame, or if some other mechanical contact exists. If you have already pulled 4 degrees from the HO table and you get any knock retard while just cruising around steady state, it is not real knock. Find the source and fix it, otherwise you'll build this great HO table that never gets used because your knock learn factor will always have you somewhere between HO and LO tables.

On my car, I don't get any knock, other than a 0.1-0.5 degree blip occasionally on takeoff from a dead stop. I have never seen any knock while cruising.

You mean nothing at all? No BKR either? I have read thread after thread looking for what is causing this part throttle KR issue. I also definitely see some burst knock on down shifts when i blip the throttle to rev match. Would love to know if i even can tune out these super short spikes and if so how? I crawled all over the engine when i was changing the plugs and discovered a heat shield bolt was missing on the exhaust manifold which i fixed on the spot. I have noticed a few thing missing or loose on this motor so far. The previous owner said that a shop here in germany replaced the blower due to failing under warranty last year and man did they leave a mess. I think I have most of it sorted now but only time will tell. It definitely ran smoother after the plugs but didnt effect the occasional KR popping up. The ones im thinking are knock arent spikes they shoot up and then slowly descend back down.

My newest issue has been doing WOT runs im not getting knock but my fuel pressure is plummeting right after the FPCM commands 65PSI my FP drops to 52 psi so i cant go forward with tuning WOT till i fix that. So i have plenty of time to play with part throttle tuning in the mean time.

Thanks for the responses.

[eLeSthree]

Originally Posted by RobZL1

I'd start by looking to see if an exhaust pipe is hitting the frame, or if some other mechanical contact exists. If you have already pulled 4 degrees from the HO table and you get any knock retard while just cruising around steady state, it is not real knock. Find the source and fix it, otherwise you'll build this great HO table that never gets used because your knock learn factor will always have you somewhere between HO and LO tables.

On my car, I don't get any knock, other than a 0.1-0.5 degree blip occasionally on takeoff from a dead stop. I have never seen any knock while cruising.

I agree, I have ZERO knock anywhere. Also running E85, and tr7ix plugs.

One thing no one has asked (maybe they already know), what is your setup? Stock car? ZL1? What octane fuel are you using?

My friend bought a used ZL1, so I downloaded his tune, and did some logging. It appeared to have been tuned. Some 02 sensor codes were turned off, 1-2 degrees of timing added, and a maf adjustment was made. I'm guessing it had intake and exhaust.

He had KR everywhere. We returned the tune to stock, changed the plugs to stock, and put some good gas in it, and KR was gone.

You can get KR from being too rich also. It's too bad we cant post data logs on this forum...

[Ammo_Don]

I get small KR spikes when shifting. I get a 5 degree KR spikes if I wot in 6th cruising. Only time I really see KR is in 6th and floor it. Not sure if that is normal or not tho

[Deutschezl1]

Originally Posted by eLeSthree

I agree, I have ZERO knock anywhere. Also running E85, and tr7ix plugs.

One thing no one has asked (maybe they already know), what is your setup? Stock car? ZL1? What octane fuel are you using?

My friend bought a used ZL1, so I downloaded his tune, and did some logging. It appeared to have been tuned. Some 02 sensor codes were turned off, 1-2 degrees of timing added, and a maf adjustment was made. I'm guessing it had intake and exhaust.

He had KR everywhere. We returned the tune to stock, changed the plugs to stock, and put some good gas in it, and KR was gone.

You can get KR from being too rich also. It's too bad we cant post data logs on this forum...

All my mods are listed in the first post 10% pulley and rotofab installed on a 2013 ZL1. Im using what is technically 93 octane in europe it is like 98 but its equivalent to US 93. No option for E85 right now germany doesnt offer it. I can get a higher octane /quality gas off base. I will be trying that next. I waiting to get my exhuast back from the shop then i will get some fresh logs to post.

[Big Biscuits]

Hp tuners? Goat rope is a good start, but does not show some simple tricks to get your log data correct. I would start with some thread search on the hp forum for history data formulas to sort out bad data. I found lots of help there. Then retune maf and VVE. If you use blended tunes(like you are supposed to), that could cause the issue. If the ecm is trying to get data from SD and it’s wrong, then the o2 trims take over, it will cause spikes. Tune the right way and it will most likely go away when fuel is correct.