Considering a forester STI as our only do it all daily car. There is a car local but it has 85000 miles and is mapped running 310bhp with 365ft lbs. Is this likely to be a ticking time bomb with the 2.5?

It won't cover many miles as I cycle to work and my wife will just use it for about town.

 

The JDM EJ255 is pretty good. My old Foggy STI was past 150k with an LPG conversion the last I heard.

 

They will need looking after, so you're going to want to see a nice thick wedge of service history, preferably by a specialist.
But they are capable of high miles.

 

Had a widetrack STI but miss the noise and the power, currently have a 2012 Legacy which is nice and massive inside but it's a bit slow.

 

The 2.5 issues appear to be more a case of if, rather than when. So they are as likely to fail at 80k as they are at 130k. That being said, I'd still budget for a full rebuild at some point during your ownership.

 

Get a better one