AutoblogGreen

I would shocked if Subaru sold an STI diesel. I would be equally shocked if they did not offer a sporty diesel version of the Impreza, at least in Europe if not here too.

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I own a 2004 Subaru Forester XT. Because of the gearing in that year, the thing does 0-60 in 5.3 seconds. It's an absolute sleeper beast.
Having awd, lots of room for my kids/dog/gear and great crash ratings make this car incredible. But the gas mileage does suck. If there's any chance of converting it to run on e85 (if it becomes available without the inefficiencies of using corn), I would keep this car forever.
However, if they offer a diesel Forester in the US, I would buy it in a heartbeat. Then, I'd chip it, give it better suspension, etc. and make my own diesel XT STi.

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I meant to also say that I would run the diesel Forester on biodiesel as I do with my 2006 VW NB TDi.

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It's quite likely that Subaru will shoehorn its new boxer diesel into every suitable platform, at least for the European market. There are indeed rumors that Subaru has a diesel Impreza STi in the works.

http://www.egmcartech.com/2008/02/22/subaru-working-on-a-diesel-impreza-sti/

However, tuning a diesel engine to deliver 180hp instead of 150hp is easier said than done, because the combustion properties of diesel fuel inherently limit engine speed. True, Audi has managed to push the envelope to 5000 RPM, but Subaru is new to diesels and its design is limited to a more usual 4500 RPM.

The only other way to increase rated power is to increase torque at high RPM. The torque curve of the Subaru diesel is artificially limited to 350 Nm (~260 lb-ft) and does drop off starting as early as 2500 RPM.

http://www.subaru-boxer-diesel.de/subaru-boxer-diesel/boxerdiesel.htm

Presumably, the single variable geometry turbo is currently optimized for low lag and high stationary torque at low RPM. The trade-off is reduced torque at high RPM, something a larger turbo can remedy. More elegant but also much harder to execute is a sequential turbo setup.

Either way, boosting power has significant implications for the cooling system of both engine and turbos as well as those all-important drive cycle emissions.

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I don't believe the diesel really needs extra horsepower if torque numbers are approaching 300 (which is as good as the current gas STi), but I'm sure a little massaging of the engine will shoot up about 10-15 more hp, but more importantly 13-18 lb-ft torque. But even if less than 10 for each, although I think they will, this will still be one awesome car! Definite keepsake in my future garageplex

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What's keeping them.
Diesel Forester for 2009 would beat the rest of the pack....I need to trade in my Outback NOW.
I need Diesel NOW.
It would be my tird Subaru.
But , if they're going to be that late I will buy a Honda CRV or VW sportwagon or VW Tiguan.
I'd rather have a Subaru Diesel.
Looking forward too, to a Diesel/Hybrid,.
What's keepin' them??????
Take my $$$$$$ now.

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