I've noticed some KR and need some advice on what to do or look at changing.
Attached is tune and logs. These logs were from track passes.
1st run you can see a little bit of knock 12 seconds in to log at just idle, some during burnout 27 seconds into log.
3rd Run it starts shortly after launch at 19 seconds into log and ramps down thru the run.
I didnt make any changes to tune except shift points at the track.
I do have a wideband and at WOT, I maintain a AFR of 11.5:1-12.0:1.
Im open to feedback as to cause of my KR and some possible things to investgiate, both tune and false knock.
This car has a cam (specs unknown but seems aggressive, as I bought with it already installed). Car is an A4 with full exhaust and LT's. I do have a lot of exhasut rattle from y-pipe banging the heat shields and floor pan.
don't forget too much fuel can cause KR also dude....chase lambda at idle 1.0 no matter what fuel type mate....I wouldn't bother with AFR readings use LAMBDA ......even at W.O.T that's a tad too rich man....if you had forced induction that wouldn't be too bad at W.O.T......CHEERS Bret....False knock mate I don't honestly believe in that because if your engine says it is KNOCKING then it really is.....Fellas if anyone thinks otherwise do yourself a favour and buy a CHASSIS EAR DEVICE and that will tell you straight away if you have TRUE KNOCK... Just my opinion/theory guys not anything else....33* timing is a lot so it could/you will be getting knock so every combo is different mate so I would reduce it to say around 24* and go from there....grab a stock timing map compare and make changes to yours even at start of map way too much timing and through out map too much of a change between rpm/cyl pressure too many troughs/dips in the 3d map dude....from your idle spark advance park/drive to your main spark map 10* is too much of a transition from say reverse to drive would cause hesitations etc.....every cam set up is different as a example when my combo was just a cam its best/most power/torque it made was with only 20* w.o.t then as I stepped it up to a bigger cam/heads/manifold etc it still only needed 22* so more timing doesn't mean more power/torque....the more efficient the heads are the less timing it will need....
30-32 degrees at WOT is a LOT of timing to be running an an LS1, so you may well be getting real knock. Cammed cars do like more timing than stockers, but I would try bringing it back to 26-28 (try a stock 1998-2000 corvette timing table, they're pretty aggressive), and leaning the fueling out to 12.5 or so. You're maxing out your injectors, but if you're running plenty rich you can probably get away wtih it. If you bring your AFR back to 12.5 or so injector duty will probably go back under 100%... you can get away with running 90 something % but it's not ideal.
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