From Livernios
Too rich can cause issues of it's own as well.
It sounds like too much, but is that the factory gauge? or an actual data log or reading from an external sensor on the dyno? My guess is if it's real the cats are melting out of it.
If the car was tuned too aggressively the catlytic converters can literally melt, causing exhaust restriction, and eventually engine damage. Sometimes this can be seen by high boost pressures, with large amounts of knock, and low power numbers. The fix, if there is no engine damage yet, is to get rid of the cats. I am not saying this is for sure what's happening, but it could be.
From Kraftwerks
We have boost (probably too much, but why?), car gets enough fuel, AFR is between 10.8 and 11.2
but we get huge knock without reason. Running only about half of the timing that it should.
Only pulley and cooler installed so fa, nothing that could make problems. Pulley must be fine as we get the boost
without any belt slippage. If something was wrong there, we would not have that boost.
Factory gauge shows even more (15 PSI). We read it out by OBD .
The cats had come to my mind also, but hard to believe that they don’t survive 5 minutes on the dyno with increase boost?
Directly after the pulley install it went great. Never run lean, had no knock. Nothing changed and no knocking all the time.
We will take the exhaust off tomorrow and check the cats
Yes, i agree with him. Too aggressive tune we can 100% exclude, I set it pig rich and with very conservative timing for the first drive.
The engine runs really smooth, I don’t see the problem with the engine.
What I can see is that the higher the rpm, the more power it looses compared to stock. That would also point towards a restriction in the exhaust
I also had somebody else check the tune, maybe I did not see something right.
But it seems to be no tune issue… We will find it tomorrow. Car needs to cool down before we can check the cats
We will have to look if some “universal” part will fit in there or if they have some special size needed.
Just replacing them with stock ones will be useless, as the issue (if there is one) would just appear again sooner or later.
But let us check first thing tomorrow if it’s the cats or if we are searching in a wrong direction.
Fact is: the knock sensors read a lot of knock which should not be there. Programming in any direction makes no changes, so we
Must look at the “hardware” side…
That not what we expected to see, but you never know
Sharp,
I think that he is learning alot about the ZL1. I just hope that they can figure this out. More to come tomorrow and I hope that its good news.
