Whats a day off good for. Working on your car.
I pulled my plugs, see attachment. All but one of them seemed overly white to me.
You tell me what you think.
Ken . . .
Spark Plugs
Whats a day off good for. Working on your car.
I pulled my plugs, see attachment. All but one of them seemed overly white to me.
You tell me what you think.
Ken . . .
The only thing that can be said is this:Originally Posted by kwhiteside
- sawtooth: this is very likely real knock (as KR decays, timing increases, knock re-occurs, repeatedly);
- single pulse: may or may not be a single occurrence of real knock.
e.g. if it really did knock, KR pulls timing which stops knock, then as KR decays timing goes back up which then allows knock again, this repeats several times or more... when you see a sawtooth pattern with say more than 3 or 4 peaks then this is what is happening;
if exhaust was banging on chassis: when engine goes to high load it leans in one direction against the motor mounts causing exhaust to bang once (maybe twice)... so going to WOT you may see a single (or maybe double) knock event as the engine initially enters high load;
you say you can't hear knock and that your spark plugs do not show any signs of overheating/knocking/detonation.
Diagnosis of knock is hard.
Do you have a closeup pic of that one plug...?
Is it just showing deposits due to octane adder...?
Does it have any metallic appearance on the ceramic tip...?
Does the ground strap look colored/discolored...?
Last edited by joecar; November 26th, 2009 at 09:40 AM.
You are welcome, and I thank you for taking time to post... and I thank mr.prick and Shawn too, this is what makes the forum......
BTW, thank you very much for working with me and taking the time to look at my tune. Prick, Joe, Shawn
Sometimes there isn't an easy answer... so just be persistent, someone will know something eventually.
Isn't that the only reason to take days off...?
Road racing is much harder on the car than drag racing...in DR you can "cheat" badly for a short time and get away with it, whereas RR is endurance-like and needs everything to be "exactly so".
I don't know how DFCO interacts with a manual transmission, but my thoughts were that maybe you want the extra fuel when you get back on the throttle, so you don't want to turn off DFCO... but I don't know.
I've tried 3 cameras and none of them take good closeups or I'm too stupid.
No spots on the insulator at all. Tips look normal. What ground strap are you speaking of?
Looks to me like knock retard occurs after an off throttle event and you leave PE mode, you have a commanded AFR of 14.1-14.6, I think. Then when you go back to an on throttle event after commanding an AFR close to stoic,you have a knock retard.
I would change B3616 to 20% for all RPM's while on the track.
I would get a cooler thermostat, 180 or 160, try Nook & Tranny, the thermostat & housing for the early LSx is about $40 delivered.
I would lower fan on temp for #1 to no more than 180.
I would look at plug heat range and consider a plug in a cooler range for the track. You are doing something most of us do not do, you are running sustained higher RPM's for sustained periods and because of that, you are achieving higher cylinder temps. Going to 14.1+ AFR on decel is just making matters worse.
I don't run a MAF tune, but it looks like you do. Your MAF curve is way different than the stock values for a 2001 Z06.
I had the same oil issues with my LS6 and the only solution is rebuild/replace. I tried everything I could think of or find, but once the oil is getting past the ring into the combustion chamber in large quantities, you're also going to get blow-by into the engine and that 2001 block you have doesn't have the capacity to equalize pressure the way the newer blocks can, so you get huge amounts of oil vapors pushed through the PCV system instead of being pulled by vacuum.
I put a simple pop off valve in my oil filler cap from McMaster-Carr that released upon any positive crank case pressure.
Good luck with it.
BTW, I'm far from expert, but these would be the steps I would take if I were in your shoes. So take it for what it is: one novice talking to another.
Oh, I meant to say the ground electrode.
Try a colder plug as SOMhaveit suggested (e.g. NGK TR6 is colder than stock).
X3. I would also look at desensitizing the knock sensors as mr.prick stated.
I have come across this same issue with a 100,000 mi statesman I was tuning. No changes in spark, mixture etc would remove the knock in this same zone. After adjusting the knock sensors the KR disappeared completely, & subsequent checks with knock phones on the dyno & plug checks showed no signs of detonation.
The Tremor at AIR
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