teppo, I suspect me and you have the same problem (you have wireless, 3G, like me?)... I always loose positions at start and restarts... I think it is because of your lag (you disappeared last night a few times . no worries on the oval as long as you drive predictably), and/or long latency (ping)...
Critical for the oval to have low pings for good starts... I am still trying to puzzle it out, but I can never stay with the pack on starts - I suspect the difference is how long control commands get to the host... maybe someone better informed than me can explain, on other tracks not really an issue, but then, milliseconds count on the oval... enough delay to miss the initial draft and then everyone pulls away.