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What do you think about this, is this possibly a false knock?
I've had some problems this summer when I replaced a larger throttle body and I've had to adjust the VE and AFR table again.
I know the P600B supercharger is loud as is the ZF.
Methanol/water injection should prevent the occurrence of knocks...and as you can see from the log, the cooling drops quickly.
Previously, when driving at full throttle, the AFR was around 11.80 at the beginning (MAP over 100) and 10.80 at the end (MAP 160)
Now the AFR has been around 12.70 at the beginning and 11.60 at the end and I have enriched the engine but maybe I need to enrich even more.
The car was tuned on the dyno last summer and there was no knock then.
Sometimes it appeared as a spike when I changed gears in normal driving.
What kind of AFR do you run the engine best without knocking?
Now there have started to be knock spikes like this in the logs.
It strikes me as odd that a larger throttle body would change the AFR that much. I think I would double check.verify the water meth mix % first-or mix with a new batch for the storage tank. I realize it's about impossible to hear if it's audible knock with the P600B or false-so I'd also think about changing the KS out too. I'm running 11.5 and richer in boost to 12 lbs with no knock-no meth/water, just an intercooler.
Interesting thing about too much ignition advance, is that the NOX % component of the exhaust gases are increased, and the problem develops that the wideband sensors indicate leaner than actual AFR (this shows up using a gas analyzer.) Learned this from a very prominent dyno tuner, as I was also running my own dynoand used a 5 gas analyzer (slow to react) in conjunction with the Wideband (fast to react but not true AFR). Many tunes and even dyno tunes have too much ignition advance and too much fuel at the same time because of this, especially when tuning using the inertial dyno (that's a whole 'nother conversation).
Another factor is that under load, ethanol content in gasoline produces higher flame speeds which is effectively more ignition timing, so MTB is at a lower timing value for the same peak pressure... except of course it's more than offset by knock resistance where timing is knock limited... but we're talking MBT timing here and the factor mentioned above.
I don't trust the knock sensor at all in my own supercharged 88. I put the trust into my fuel, intercooler and tuning. I do pull some spark advance preemptively as a function of IAT using my MAF sensor's integrated IAT which located downstream of the intercooler.
I see knock counts in the lower gears especially during wheel spin, but typically not in high gear/high load when the car is hooked up where it should be more likely to knock.
I don't trust the knock sensor at all in my own supercharged 88. I put the trust into my fuel, intercooler and tuning. I do pull some spark advance preemptively as a function of IAT using my MAF sensor's integrated IAT which located downstream of the intercooler.
I see knock counts in the lower gears especially during wheel spin, but typically not in high gear/high load when the car is hooked up where it should be more likely to knock.
Thanks again for the tips
I am also of the opinion that the knocks coming from a low gear are probably false.
But I adjust the AE and VE table and yes it will be good then
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L98 Procharger P600B false knock?
