duncanm

I suggest you contact these guys. Lambda Tuning: https://lambdatuning.com/services/ They're literally just down the road from you. https://lambdatuning.com/2016/12/18/jdm-legacy-bebh-base-maps/ (or maybe that's who remapped your car for lower octane.. ?) Silicon on the IC pipes is a definite win for very low $$..

read the attachment here: http://www.subyclub.com/topic/2416-handy-ej20tt-stuff/?p=590699

vent install for small (52mm diam.) gauge.

yah what? It answers your question regarding oil flow.

http://lmgtfy.com/?t=i&q=subaru+boxer+oil+circulation

also check your ECV adjustment.

feels like the rear is jumping sideways when you're driving in a straight line and hit a small bump. (I say 'feels like' - because it actually is)

Shot diff bushes is usually a clunk on/off the throttle. It adds slack to the drivetrain. Trailing arm you'll get some funky handling - tendency for the rear to skip offline on bumps, for example. They're all easy enough to inspect - get under there and have a look.

I reckon it probably took me 7 hours to do the whole rear end of mine without a press in the driveway. Seems excessive for a mech with a hoist and press...

Just jam some poly diff bush inserts in if you can't be arsed pressing them out. Rear trailing arms really should come off if you want to press in genuine jobs, but you can also just knock out the old ones (drill + hacksaw) then pop in poly ones. The others (lateral arms etc) are 'easy enough' to remove, press out & replace with rubber. (actually, I found removing and pressing in new a c*** of a job without a shop press). Its a lengthy process, so exxy if you get a mech to do it ($1k is not unreasonable).

n/a, snail?

https://web.archive.org/web/20150315151154/http://www.veloce.pwp.blueyonder.co.uk:80/Otherttdocs/twin_turbo_diagram.htm https://web.archive.org/web/20150315144936/http://www.veloce.pwp.blueyonder.co.uk:80/Twin Turbo Operation/ttopprt2.htm https://web.archive.org/web/20150315063723/http://www.veloce.pwp.blueyonder.co.uk:80/technical 1.htm https://web.archive.org/web/*/http://www.veloce.pwp.blueyonder.co.uk:80/TT PDFs/*

one other thought about steering which is easy to check - inspect your steering rack bushes. A few years of oil splatter can make them go to mush and fall apart, then the rack slides about. You'll typically feel this on turn-in, though. Feels like steering slips as it loads up.

could be two unrelated things. pop it up on stands and idle it in gear - poke around with a mechanics stethoscope (broom handle or similar) to work out where the noise is coming from. Maybe its gearbox or centre diff bearings. Wandering could be rear-end. Rear trailing arm front bushes shot, for example.

'round town I typically get about 11.5l/100km. So about 450km before the light comes on and I refill (~48-50l) It'll rise drastically with a heavy foot, or go as low as 9 cruising on the highway. This is a RevB 208 in a short-ish geared BH outback. Secret is to try to keep it off boost. Its definitely an art of twitching your toe rather than using the foot.