Persistent knock retard on e85 flex tune
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I was waiting till I got this squared away. It has taken months . It is my next project (January) but my faith in flex is not the best at the moment.
I get it, I would want to wait until I knew it was safe as well. I hope you get your current build all squared away. Good luck, Sir! Any updates?
I ultimately found help from one of our very helpful forum members 16gomango that solved the issue. My tuner was not really willing to offer much in the realm of trouble shooting. After ruling out mechanical issues I had to tweak the knock sensor values around that range and the big timing pull went away. Drives great now and I have had no issues with around 500 miles. I never see more than 1.5 V from the knock sensors on the logs and only at that one spot so I do believe it to be false.
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What tuner so I know who not to call...
Not if you can safely determine it is a false knock area, and only set it low enough to not pull timing in that area. That's my understanding anyway.
No. You need to correct the false knock. Those knock sensors are not for show. You need those working correctly to pick up the real knock that you might not see in crap DA, but you get a negative DA day at the track and might bend a rod when you otherwise didnt know you were on the edge.
You might have too hot of plugs. You might have a header dinging off the body or something near enough the motor. There are lots of possibilities and NONE of which should be solved by lowering the knock sensor sensitivity.
Im glad you got that squared away! Are you planning on running a similar tune for your TRX?
What tuner would you recommend?
Or you simply swapped pulleys like OP and now the factory tuning of the knock sensors no longer matches the base harmonics of the supercharger. Adjusting the knock thresholds to account for this is a well accepted and safe practice. Go back and read this very thread. I posted logs from my personal car that I personally tune.
You also grenaded your stock motor, so no I dont think I will be taking tuning advice from you.
You spout off in a lot of threads like a know it all. You need to do more research before posting. Just makes you look like like a dumb ass.
That was from spinning it too high of rpm wasn't it, before we knew the powder forged rod weaknesses? Not necessarily tune related?
Yeah and you still grenaded your stock motor "speedy". So yeah take my dumbass spout off advice to not lower the knock sensors, or take your "I blew up my own motor" advice and lower the knock sensors... Yeah Im the dumbass...LOLOL
Ahahah WAT?? You cant overspin a motor without a tune. And if speedy is tuning his own car, I'd expect it was tune related...LOL
Who knows really. I actually had dealerships reach out to me that had bone stock cars break the cyl 7 rod and several other owners as well with the same cyl 7 failure. Seems it is (or was) a weak point for some reason. Car was at 800rwhp at the time.
Yeah, I thought I remembered reading a while back that it was suspected a weak rod. It's my understanding that those powder forged rods don't like to go much faster than 6700 rpm and the downstroke at those speeds seems to find their weakness.
Well, mine's a 2016 and the tunes were pretty hot from the factory for the first couple of model years. I have logs from my car bone stock on 93 octane getting consistent 4° of STKR at WOT. I was shocked to see that but like everyone else at the time thought "well must be fine or they wouldn't have tuned it like this". Some would say must be false knock but I'd put in 109 octane race fuel and it would go away. Definitely wasn't false. That could have weakened something for sure.
The rod bolts were also upgraded in 2018 (I think it was 2018 maybe 2017). So engineering obviously saw something there. Between that and the tune changes we don't hear of engines failing now, at least I haven't.
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