Alright, so I played with the settings of the DSATX a bit more and I am quite confused.
The ACCTIMEVAL not only seems to affect the time it allows to crank the engine, but also the delay before the DSATX will will start the PC (and I think even shut it down).
So if I put in a value of 150, it will give me time to crank the engine 1.5 secs before it will turn off my PC, but it will also cause a delay of 1.5 secs before the PC is started after I turn on the ignition, and also after I turn off the ignition before the DSATX turns off the PC.
Is there any way to separately adjust those times?
I tried the other options like TURNONDELAY, TIMER1EE or VOLTSTHYST, but those dont seem to override what ACCTIMEVAL does, nor do they help if I leave ACCTIMEVAL on the default value.