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I prefer to live life dangerously..

Has started doing the rounds on facebook, contact owner if seen. Number Plate MADSTI, standard looking v4 coupe with black wheels

@YoungOne this is absolutely disgusting. I feel for the guy man. I get so irate about theft in general. Takes the lowest of the low to steal from someone. Such an invasion of personal space and trust. Makes me so mad. I was recently thinking of approaching the local police an offering to use my car to sting these scumbags. Seriously, I'm so over it. @IZichard Agree, maybe the only way is to GPS every car. But even then, there will always be ways around it. Like you said too, where are all the parts going? Facebook is as good a black market as anything but I don't typically see high profile parts on there. Are they being shipped off overseas?

So I have been giving some thought over the weekend to why stock location turbos on Subarus always deliver relatively mediocre results. Why is it that turbos that routinely deliver 300wkw+ when installed in a rotated/twisted setup (i.e. GT/GTX3071R) get more like 250-260wkw when installed in the stock location? I believe the answer is all in the turbine housing. In order to retain "stock" fitment, the turbo cannot alter the relationship between the location of the uppipe flange and downpipe flange. This in turn forces the position of the turbine wheel; this is also forced by the location of the turbo's inlet having to go under the intake manifold. Because these locations are fixed, there is a hard limit on the size of the volute (the channel the exhaust gas takes through the turbine housing), which also limits the size of the turbine wheel. Furthermore, if you increase the size of the turbine wheel you take up space that is needed for the volute, so you just shoot yourself in the foot - either you have a big, high-flowing turbine wheel and feed it with a straw, or you open up the volute and then choke it at the turbine. This gets a little bit disguised by manufacturers claiming, for example, that their stock location GTX3071R has a 0.84AR turbine housing, but this is simply a ratio of two sections of the volute, it has nothing to do with the actual size of the housing. I guarantee you a bog standard Garrett T3 0.84AR housing for that turbo has a way, way larger cross-section. Twin-scroll does slightly resolve this, depending on the turbo, as you can have two volutes side-by-side and thus gain considerably more area. When you choke the exhaust flow you end up with high pre-turbine exhaust backpressure; I have a theory about this causing exhaust reversion at certain boost/EBP levels where the exhaust valve spring pressure isn't high enough to completely close the valve, causing knock and crap power. EDIT: Side note on why US cars seem to do better on stock location: completely aside from how half their dynos are just complete works of fiction, I believe that a lot of the US "stock location" turbos just completely ruin the position of the downpipe; something we can't do because of steering/brakes components in that area, and then they just don't talk about how none of the downpipe brackets line up any more and the midpipe fitment is a bit S***. I tried to install a US-spec "stock location" turbo once and the fitment was utterly S***. Feel free to tell me I'm dumb

Yep...the 300kw one i think? Too much of this going on lately!!

Was that the same one on TradeMe not long ago for around 30k?

i really need some diagrams with force vectors and such up in here doc.

The other thing to factor in is that they are 30 year old thrashed to death pistons.

I can see the problem, your 4 is inline.