Data logging advice
#1
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Hey guys,
I'm trying to tune out some of my random knock events. I'm not getting too consistent readings so far. Not sure if my exhaust rattle is causing any of it or not. Is it normal to sort my data by RPM to see similar areas of RPM x MAP and try and rule out real and false readings? Here is what I have. It's about 15 minutes worth of logging. And yes, my AFR is not at the ideal point yet, but I'm getting there. I am using 94 octane with 11*C ambient temps.
https://spreadsheets.google.com/ccc?...QblFBQ2c&hl=en
I'm trying to tune out some of my random knock events. I'm not getting too consistent readings so far. Not sure if my exhaust rattle is causing any of it or not. Is it normal to sort my data by RPM to see similar areas of RPM x MAP and try and rule out real and false readings? Here is what I have. It's about 15 minutes worth of logging. And yes, my AFR is not at the ideal point yet, but I'm getting there. I am using 94 octane with 11*C ambient temps.
https://spreadsheets.google.com/ccc?...QblFBQ2c&hl=en
#2
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That's 15min of logging? And you only have 351 data points? That's only a 0.4hz sample rate. Or did you uniquify some of the redundant RPM data points? What are you data logging with?
I don't fully trust my 13hz logging with the Hydra ems since I always wonder if I could be missing a knock event in between sample points. However, I guess if the knock is persistent it will eventually show up in the logs.
I don't usually sort by RPM but that is an interesting idea. I usually just ignore events below a reasonable noise threshold. Though I always get minor spikes especially just after letting off from being in boost. I've always assumed these spikes were noise from drive train shock. And they are hard to identify if the log is not left sorted with time.
I don't fully trust my 13hz logging with the Hydra ems since I always wonder if I could be missing a knock event in between sample points. However, I guess if the knock is persistent it will eventually show up in the logs.
I don't usually sort by RPM but that is an interesting idea. I usually just ignore events below a reasonable noise threshold. Though I always get minor spikes especially just after letting off from being in boost. I've always assumed these spikes were noise from drive train shock. And they are hard to identify if the log is not left sorted with time.
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Sorry, it's 15 minutes, but I only kept the upper half of the rpm range in this spreadsheet and did not delete same rpm points. The lower half or more, had 0 knock. I am logging with my Adaptronic ECU.
I get a lot of knock events when I hit the rev limit. I'm sort of assuming it is from all the back firing up there. I have ignition cut only during rev limit.
I know what you mean about the missed knock events. I was wondering the same thing, but if it was bad it would probably show up. I don't really know if sorting by rpm and comparing load x rpm is valid, but I'd like to get some inputs.
I get a lot of knock events when I hit the rev limit. I'm sort of assuming it is from all the back firing up there. I have ignition cut only during rev limit.
I know what you mean about the missed knock events. I was wondering the same thing, but if it was bad it would probably show up. I don't really know if sorting by rpm and comparing load x rpm is valid, but I'd like to get some inputs.
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You might be able to get more input if you had a Mod move this to the ECUs and Tuning sub-forum.
I assume that the Adaptronic has a programmable knock threshold that you've already set up?
You might also want to post your spark map and see what people think.
If you're not getting consistent results then I'd speculate that it's influenced by events leading up to the knock events. And sorting based on rpm loses that information. Hopefully more experienced tuners can provide their input.
I assume that the Adaptronic has a programmable knock threshold that you've already set up?
You might also want to post your spark map and see what people think.
If you're not getting consistent results then I'd speculate that it's influenced by events leading up to the knock events. And sorting based on rpm loses that information. Hopefully more experienced tuners can provide their input.
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