I'd guestimate that it is just the difference of the centre/rear diffs compared to the open wrx ones allowing you to power out a more than normal. Check what rear diff was put in (1-way, 1.5-way or 2-way) as that may be the reason, doubtful but never know. Otherwise get the workshop to check and/or have your alignment/tyres checked.

Must say, I haven't had the car's back end whipping out at every round about unless I was trying to do it.

I'd suggest re-visiting driving style until you know what's going on!

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[COLOR="Gray"]550Nm off a 2L... Just wish it was in the dak dak...[/COLOR]