Subaru diesel and hybrid news

[neg_matnik]

Originally Posted by Tea cups

I don't get your argument. If it is the same displacement turbo diesel in a vehicle of similar cost to the Forester turbo diesel, why couldn't you compare the torque characteristics of the two motors? That is like saying we can't compare Evo and STi motors because they don't make the same HP.

I would expect a 180HP diesel engine to churn out significantly more torque than a 140HP diesel engine. I'd expect the 140HP engine to feel weaker over the entire rev range. With such a limited rev range, a 40HP power difference is massive and pretty noticeable (28% power advantage for the 180HP engine). So, yeah, we can always compare torque characteristics, but, IMO, there would be no surprise regarding a 140-HP Diesel engine vs a 180-HP Diesel engine.

Now, I'd be more interesting to see a torque output comparo between a 2.0L 140-HP VW TDI engine and the 140-HP Subaru boxel Diesel. Then we could confirm whether or not the initial low RPM torque output of the boxer is any weaker. That's just what I'm saying .

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[neg_matnik]

Originally Posted by Cardiff Giant

On Top Gear James May drove a Legacy diesel for their "one tank of diesel to go from France to Blackpool" and before the race Clarkson said something about the boxer diesel not developing much torque/power until you hit 3rd of 4th gear which sounds oddly like my 2.5L NA gas engine (third and especially 4th are when it really comes alive) so I think it may just be people who aren't used to the boxer who are making this statement.

Yes, this could be. There's an article here explaining how Subaru engineers recognized that the Diesel boxer engine was not producing enough torque below 2500 RPM (compared to competing 2.0L inline-4 Diesel engines) in early development stages. They supposedly found a solution for this problem and improved torque output below 2500 RPM. See below:

http://www.boxerdiesel.com/engineering/en/04.html

[HB_Dad]

H6 3.6L Diesel FTW!!!

[HB_Dad]

SOA_Blog, is there any chance we may see the advantages of both of these tied to one system, mainly a hybrid diesel?

[BrysImpreza]

Hey SOA Blog,

Use the hybrid design I sent Subaru of America over 4 years ago dammit! All I got back was a stock "Thank you for your future interest in Subaru products" notice.

[Cardiff Giant]

Originally Posted by neg_matnik

Yes, this could be. There's an article here explaining how Subaru engineers recognized that the Diesel boxer engine was not producing enough torque below 2500 RPM (compared to competing 2.0L inline-4 Diesel engines) in early development stages. They supposedly found a solution for this problem and improved torque output below 2500 RPM. See below:

http://www.boxerdiesel.com/engineering/en/04.html

Good info, Clarkson seemed to think it was partially a trait of the boxer engine (not just the diesel) and anecdotally I find the same to be true in my OBS (3rd,4th, and oddly even 5th being where the powerband really comes through) . I don't know enough about engines/gear ratios to explain it but do others find this to be true as well? Perhaps if it's something inherent in the design anyway, the diesel makes the problem more noticeable, or like I said earlier it's more obvious to people who are used to driving diesels from other manufacturers.
I'm sure a boxer diesel would be just fine for me coming from the 2.5L NA.

Here's the clip in question where Clarkson and May discuss the boxer diesel a bit right at the beginning. It's an entertaining clip throughout so I recommend the whole thing if you've not seen it before.

StreetFire

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[Beaverboy]

Originally Posted by Cardiff Giant

Good info, Clarkson seemed to think it was partially a trait of the boxer engine (not just the diesel) and anecdotally I find the same to be true in my OBS (3rd,4th, and oddly even 5th being where the powerband really comes through) .

Taller gears don't improve the powerband unless you're running a huge turbo that won't spool in the lower gears.

[kage]

Good news, and yet disappointing. I'm really looking to upgrade the current family car within the next year or two, and a diesel Forester or Outback would have been high the list, as long as they came with the 6 speed manual.

I wonder if they'll do a dedicated hybrid vehicle a la the Prius, or just add a hybrid powerplant to an existing car? Economically it makes more sense to do the latter, but appealing to the smug crowd is important in that segment.

[mattejb]

Well I think the new Subaru/Toyota coming out would do great with a hybrid.

[GuyLR]

[quote=neg_matnik;26809175]
Now, I'd be more interesting to see a torque output comparo between a 2.0L 140-HP VW TDI engine and the 140-HP Subaru boxel Diesel. Then we could confirm whether or not the initial low RPM torque output of the boxer is any weaker. That's just what I'm saying .[/QUOTE

The Subaru 2.0TD makes 148 hp not 140. The big deal of course is the peak torque and it's apparent willingness to rev and smoothness that has been reported in the press. I take that to mean that it will be more fun to drive than lower revving diesels. I also expect that a sport tuned version in the 170 hp range is possible.

[Tea cups]

Originally Posted by GuyLR

The Subaru 2.0TD makes 148 hp not 140. The big deal of course is the peak torque and it's apparent willingness to rev and smoothness that has been reported in the press.

I'm not familiar with the powerband of the competing diesels, but edmunds' inside line (american press) test drove an 09 Forester 2.0D 6-spd MT and said the power dropped off dramatically after 3600 RPM and that reving much past that was essentially useless.

[SOA Blog]

Originally Posted by BrysImpreza

Hey SOA Blog,

Use the hybrid design I sent Subaru of America over 4 years ago dammit! All I got back was a stock "Thank you for your future interest in Subaru products" notice.

tbh - it was probably destroyed without reading. We are not allowed to recieve that kind of soliciation for legal reasons.

[WRick]

Just bring us the damn cars. *

* = Speaking for everybody in one of the largest canadian suby dealers.

[impRSa]

http://www.wired.com/autopia/2009/05/subaru/

Fuji Heavy Industries, which owns Subaru, plans to offer a hybrid based on the technology that underpins the Toyota Prius.

The two automakers have long had an alliance to share vehicle development, production and supplies. Ikuo Mori, president and CEO of Fuji Heavy, says his company will draw on that partnership to offer a gas-electric vehicle.

“We will take advantage of our alliance with Toyota,” he told reporters in Japan, according to the Wall Street Journal. Toyota owns a 16 percent stake in Subaru, but so far the partnership hasn’t borne much fruit when it comes to gas-electric. One industry insider told us Toyota, which holds 80 percent of the hybrid market, has been reluctant to share the technology.

The announcement follows the Obama Administration’s plan to significantly tighten fuel economy and emissions regulations. The rules, brokered with help from the auto industry, increase the average fuel economy of new cars and trucks to 35.5 mpg within seven years and cut tailpipe emissions by almost 40 percent.

Mori said Subaru also is developing a new diesel engine to meet those emissions rules and will offer it in 2011 or 2012. He did not say which models might get the new drivelines.

Subaru also is testing an electric car, the R1-e (pictured) with an eye toward a possible U.S. release.

[Tea cups]

Originally Posted by impRSa

The two automakers have long had an alliance to share vehicle development, production and supplies. Ikuo Mori, president and CEO of Fuji Heavy, says his company will draw on that partnership to offer a gas-electric vehicle.

Why are all these hybrids using gas engines? It would seem a diesel hybrid would be the best of both worlds -> diesels' main advantage is highway mileage (and still better than gas in the city) whereas as hybrids' main advantage is city mileage.

[neg_matnik]

Originally Posted by Cardiff Giant

[...]Here's the clip in question where Clarkson and May discuss the boxer diesel a bit right at the beginning. It's an entertaining clip throughout so I recommend the whole thing if you've not seen it before.

http://videos.streetfire.net/video/T...-To_201551.htm

That was very interesting and entertaining . I can't believe Clarkson made it all the way to Blackpool in the Jaguar (with still some Diesel fuel left in the tank ). The little BlueMotion Polo made it with only 10 gallons (US galloms? British gallons?) in the tank ... The Legacy Wagon made it too despite a detour. All 3 vehicles have been really impressive in terms of fuel consumption. We badly need more vehicles like these in the US.

[neg_matnik]

Originally Posted by Tea cups

Why are all these hybrids using gas engines? It would seem a diesel hybrid would be the best of both worlds -> diesels' main advantage is highway mileage (and still better than gas in the city) whereas as hybrids' main advantage is city mileage.

Yes, Diesel-electric hybrids would return outstanding fuel mileage in all types of driving and they would probably be a blast to drive too.

[rsholland]

Ferrari is working on an AWD hybrid sports car. The gas engine will power the rear wheels, while electric power will be used on the front wheels.

http://forums.nasioc.com/forums/show...7#post26821617

I'm hoping Subaru might consider something like this for their joint-venture coupe (yes, I still want to see an AWD coupe to be offered along with the RWD version), which appears to have the engine located well behind the front axle.

Bob

[whoosh]

they seem to always beat up on the prius

let them adjust the diesel mpg to reflect the difference in price between gas and diesel.

then they should do a city mpg test between the diesels and a prius.


i think we know which will win

[WillRX]

I think I can contribute to this discussion. I own two diesels, my Legacy and a Skoda Fabia VRS with a 130hp 1.9L TDI. The Skoda has been remapped and is making probably around 150 horsepower now.

The Skoda is a small car, and much zippier off the line. The remap allows the engine to rev to redline much faster, but power still trails off substantially after 3500-4000 rpm. As it is a 6 speed, it is almost impossible to keep up with the engine as you find yourself shifting all the fricken time (and fighting a fair amount of torque-steer, especially in the lower gears). It is a fun front-wheel drive car that regularly gets me about 42-43 US mpg on my usual drive of curvy country roads, with occasional city driving.

The Subaru has a very linear powerband, which, especially after the Skoda, makes it feel like its lacking low-end grunt. Being a heavier car, the sensation is much more train-like, with all 4 wheels getting up to speed a little slower, but with power that continues to build (almost) to redline.

The ratios of the 5 speed are well chosen, and while downshifts to pass are more necessary than in the Skoda, the overall driving experience is a lot more relaxed. I can hit 90 kph (speed limit on back roads) in second gear, and can cruise leisurely in 5th at that speed, or push it hard in 3rd or 4th on the twisties. I average 40 US mpg on the same roads, which I find really impressive for a heavier car with AWD.

I have driven the 6 speed with the diesel in both the Impreza and Forester, and the ratios were slightly closer 1-5 with 6 feeling like a strictly highway gear. Not bad, but I much prefer the 5 especially as I don't do a lot of highway cruising.

Lastly, Subaru engineers said the diesel was good for up to about 180hp, but as it was their first diesel, they decided to play things conservatively to see how the engines would hold up, and also to meet european CO2 levels that don't penalise new car buyers.

I'd be happy to answer any specific questions you might have about this engine. I am truly impressed with it, and while I never forget it is a diesel (especially on start-up and/or with the windows down), I do sometimes forget to shift and find myself driving along at 90kph, 4000rpm in third, because the engine is so smooth.

Will

[rsholland]

Originally Posted by WillRX

I do sometimes forget to shift and find myself driving along at 90kph, 4000rpm in third, because the engine is so smooth.

Will

Ah, another candidate for a digital gear indicator/reminder. The new 2010 6-speed Legacy and Outback have just such a feature.

Bob

[BOY]

To all the "Why Subaru don't hybrid" people out there, the TPH system that they developed made great power and had good MPG but it was a parallel hybrid and not an answer to long term green motoring. The Honda IMA is the same type of setup and requires the gas motor AND electric motor to run in tandem.

The Prius uses ToMoCo's HSD which allows both parallel and series operation of the hybrid system. The Volt's hybrid system is series only and uses the gas motor as a generator. The proposed Subaru/Toyota hybrid will likely be a HSD application to the boxer engine and AWD. If Subaru works on its turbo fuel econ (miller cycle, direct injection, etc) it should be a huge winner. With Li-ion replacing NiMH the elec motor should be able to provide much more torque to the equation and be a killer combo.

[neg_matnik]

Originally Posted by whoosh

they seem to always beat up on the prius

let them adjust the diesel mpg to reflect the difference in price between gas and diesel.

then they should do a city mpg test between the diesels and a prius.


i think we know which will win

At the moment, Diesel is around $0.10 cheaper than regular gasoline around here (SF Bay Area). Someone from the San Diego area has reported the same price difference. As I've been saying a couple of times, Diesel fuel prices vary a lot depending on the location. A Prius will return better MPG in the city but an equivalent Diesel powered car will return better MPG on the highway. But, then again, people just need to decide which type of vehicle is better for them depending on the kind of driving they're doing.

[rypt]

Originally Posted by neg_matnik

A Prius will return better MPG in the city but an equivalent Diesel powered car will return better MPG on the highway.

That is true; however you can get a smaller diesel car (say a Polo instead of a Golf; or a Focus instead of a Fusion) but you cannot get a smaller Prius.
The diesel/bluemotion Polo (and nicer trimmed Seat Ibiza) both beat the Prius on mpg figures

[Mike Wevrick]

Originally Posted by Tea cups

Why are all these hybrids using gas engines? It would seem a diesel hybrid would be the best of both worlds -> diesels' main advantage is highway mileage (and still better than gas in the city) whereas as hybrids' main advantage is city mileage.

cost mostly; Mercedes does have a diesel hybrid coming though