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Here is the car,
2010 Camaro 416 stroker, 9.3:1, stock heads, blower camshaft, 3.6LC Kenne Bell @9psi.
13 degree timing, .76 lambda, 138 degrees IAT, Shell UTR115 fuel, NGK 8's, and still getting knock.
Car runs great, no weird engine noises, just cant keep it from knocking. It is audible!!
This thing is kicking my butt. Anybody have anything similar to this? I don't know what else to do at this point. I have tried .70 lambda and it still knocks.
Pull the plugs. Are they clean?
here is a new plug after the pull in the log...
oh here is the calibration...
Ever done a case relearn? Sounds like the overall timing may not be quite right. For only 9 pounds of boost and that sort of compression you should be able to run 16 without it knocking. Especially on that good of fuel.
I run the same blower setup on my Silverado and on the meth run 24* on 13 pounds of boost.
I havent.... i'll try that... at this point i'll try anything lol
Case relearn didnt help... just install another AFX, so i'm watching both banks, which are staying within 1% of each other. Just tried 8 degree of timing with .70, .75, .78, .82 lambda and it knocks the same regardless. I'm think it is some type of mechanical issue...
^ you wouldn't happen to have the cam specs by chance would you? Even with a broken piston or something to that degree, 8 degrees it should not knock at all.
And you're sure the knock is audible? I know it's a lot to ask but can you make a short video of it on the dyno so we can hear it?
It's a possibility you might be hearing something else (although pre-det is its own definite noise) and all you need is to desensitize the knock sensors a bit because of whatever headers are on the car.
Plug looks oily too. What kind of PCV setup is on the car? Got a ton of oil in the intake?
Not very much in the intake at all, we are using the pcv that comes with the KB. The knock is very audible... windows ups and quite exhuast its is pretty clear it is knock, although i don't think i could differentiate between pre- det and det. Kook headers... normal stuff. We just did another car just like this, 2.8, stock motor, same exhuast, no knock and made good power with the right amount of timing. We are currently doing a CLT and compression. After that if we dont come up with anything i can video the noise. Thanks for tasking interest!!
Well... CLT and compression passed with flying colors...
A long shot but a flat cam could cause this. Too much Dynamic Compression, or collapsed exhaust lifter. Basically anything that raises the moving compression in a cylinder. It doesn't miss or anything like that does it?
nope runs "perfect." I'm thinking along your line... unfortunately..
Strokes chin. My 417 is at 9.5:1 cr with WCCH Cadillac LSA heads. And my cam is a 236/245 .617/.612 on a 114. Just for reference. About 1 year ago Conp had a bad batch of cams that went out. I got one of them in my G8 and it trashed my 364 in my G8 last month.
Cam is a very plausible problem that you could be facing.
Might be, it is a Bullet Billet blower camshaft, so i would have to have one of the rollers on a lifter giving me an issue, those billet core are pretty dang tough.... but then again no misfires or weird sounds. oil and inside of oil filter look perfect. Without pulling it all apart i'm just at a loss.... Just not ready to commit to pulling it down lol
Disconnect any sort of PCV from the blower inlet and run it for a bit, then change plugs and make a WOT pass. See if it gets getter.
Good idea but no luck, still detonates. Here is the log
Get a can of brake clean and check the intake for leak`s.
U sure its not an exhaust leak if it runs great? Or a clogged injector and puddling up
Or u may have a weak coil or I've had a brand new plug the porchlen on the plug would slide up and down on the plug so when we took the plugs out and looked at them it was fine but when u would go to put the back in it would slide down the electrode would close the gap and this was on my grand national but I would really inspect the plugs turn them up and down to make sure they r good! U have to love boost
Or a loose Knock Sensor like I had on my Silverado and traced it for 2 months. All good when tightened.