VersaTune User Forum

Hi there guys,

Long time not visiting this forums!

I'm experiencing a weird issue, and it is driving me mad, these are my WOT AFR tables:



As you can see in my following logs only OL Knock table is targeted:

Datazap with complete log

What in the heck is happening here? Am I missing something? I think that same situation is happening to my CL tables and Ignition tables.

Any idea?

Cheers.

Hey!

Take a look at the "Ignition -> High BAT/ECT retard no knock" table and see where the current BAT temperatures throw your timing values. You will not see these values as knock retard in your logs as it happens sometimes with the overload retard or when you approach the fuel cut boost limit protection. But you will see them in the actual timing and how far is it from the target timing in the normal/overload timing tables.

If your current tune is not the intellectual property of an e-tuner you can try posting it so that we can take a look at it while having the .csv log file handy as well.

mituc wrote:Take a look at the "Ignition -> High BAT/ECT retard no knock" table and see where the current BAT temperatures throw your timing values. You will not see these values as knock retard in your logs as it happens sometimes with the overload retard or when you approach the fuel cut boost limit protection. But you will see them in the actual timing and how far is it from the target timing in the normal/overload timing tables.

Confirmed, is that, ignition at 6.500 rpm. is 10,22º but 60ºC BAT and 90ºC ECT has retarded my ignition 3,5º so it's OK. Sorry, I suspectful of everything after seeing my fuel tables not followed as I was expecting. Thanks @mituc for point it out.

As I said before, I'm pretty sure that only my Knock fuel tables are targeted by my ECU. Is it normal? What's wrong?

BTW, my tune is ported from AccessPort, ain't those axis titles inverted in this table? [stock version]:


In VT it looks like this [stock version]:

keridil wrote: As I said before, I'm pretty sure that only my Knock fuel tables are targeted by my ECU. Is it normal? What's wrong?

When the ECU starts pulling timing based on the high BAT table(s) it will also enrich the mixture. So that is why the AFRs are richer than the actual target value. And when that happens, when you look at the logs it's pretty easy to mistake the actual AFRs with the stock knock values because they will be very close indeed.

Also, given the high BATs you are running into you could really use a WMI kit even with a small nozzle only for cooling (like DO3/DO5). I pushed my car up to 7000rpm in relatively warm weather with BATs around your values but a bit higher boost and airflow values (340-350g/s), and ended up with cracked ring lands in pistons #2 and #3 because of the heat. Injecting a light alcohol mix (40 alcohol/50 water, or 50/50) no matter if it's methanol (the Europe regulations make it harder to acquire in pure form) or just 96% alcohol which you can find in food stores or even hypermarkets like Carrefour/Auchan sometimes can help a lot both with power and engine reliability in time.

mituc wrote:When the ECU starts pulling timing based on the high BAT table(s) it will also enrich the mixture. So that is why the AFRs are richer than the actual target value. And when that happens, when you look at the logs it's pretty easy to mistake the actual AFRs with the stock knock values because they will be very close indeed.

OK! That is something that I didn't know. So to remove that kind of mistake I can try to neuter those high BAT tables and relay again in fueling tables to remove knock just to confirm that what is happening is what you said. I will be cautious.

mituc wrote:Also, given the high BATs you are running into you could really use a WMI kit even with a small nozzle only for cooling (like DO3/DO5). I pushed my car up to 7000rpm in relatively warm weather with BATs around your values but a bit higher boost and airflow values (340-350g/s), and ended up with cracked ring lands in pistons #2 and #3 because of the heat. Injecting a light alcohol mix (40 alcohol/50 water, or 50/50) no matter if it's methanol (the Europe regulations make it harder to acquire in pure form) or just 96% alcohol which you can find in food stores or even hypermarkets like Carrefour/Auchan sometimes can help a lot both with power and engine reliability in time.

Oh, same issue happened to me but on a K04 and only at 290 g/s, ring lands in pistons #2, #3 and #4 were cracked. I'm planning on that WMI thingy too. I've access to methanol in Spain and to Tolueno to mix into my tank to help avoid knock too.

set all your fueling tables identical to prevent table hoping issues. the Ecu will pull fuel for knock regardless of what is in your knock tables.