Can anyone enlighten me and tell me what type of exhaust a 1994 WRX has as standard - i.e. does it have a round 3" or 4" tail pipe or oval/twin pipe as in the UK.

Is yours an import? as the japs love to put on great big oval exhausts and a lot of them reach us like that. My guess would be the twin pipe style.

As standard,a twin pipe rear silencer was fitted,or at least that was what was on mine until I changed it.
Regards
Dean