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Subaru Legacy/Outback 2005+

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Comments

  • sdufordsduford Posts: 577
    "Keep in mind it's only FWD, too."

    Actually I tested the AWD version, which is obviously a tad slower than the FWD version, but it has no torque steer.

    Given where I live, I absolutely need AWD or I can't get home in the winter. Also, after the remnants of hurricane Floyd dumped 5.5" of rain on us in 12hours and wrecked our dirt road, I realized that I need high ground clearance, so the S40/V50 is now out of the running.

    I am left with only the Outback and the XC70, but I find the XC70 drives like a big Buick. While the VOlvo has a superb interior and is extremely comfortable, the Outback feels much more stable and nimble.
  • saedavesaedave Chicago, ILPosts: 679
    Note the different horizontal rpm scales. The H-6 is plotted down to about 1200 rpm and the H-4T to 1600 rpm. If idle rpm is around 750, off idle H-6 performance might be much better than the turbo. My own test drives of both produced a pronounced preference for the H-6, but it is a shame that the great brakes and handling of the GT are not included.
  • kenskens Posts: 5,869
    Continuous AWD on MT vehicles uses a viscous coupling (VC) to send power to the front and rear axles. The VC acts like a limited slip differential. When the front and rear axles start spinning at different rates (indicating slippage), the fluid in the VC starts the thicken and forces the front and rear axles to spin at the same rate.

    The entire process is completely passive with Continuous AWD. The unit is tuned to split power 50:50 and to allow some amount of slip before it starts to lock up to enable turning. Basically, you need some wheel spin to get the system to work. It's a very simple, yet effective system that's been in place for years. Since the power split is normally 50:50, you have less chance of ever encountering wheel spin vs. a FWD/RWD car.

    With VTD, power is normally split 45/55 (the rear bias is there for a better handling) using planetary gears instead of a viscous fluid. In addition, VTD uses an electronic clutch pack that can vary the power from that default bias (the exact amount escapes me).

    The main advantage of VTD is that because it is electronic, it can react faster and more efficiently with the vehicle. For example, sensors on the vehicle let it know when one is either accelerating or braking and can send more power to the necessary axle (ie. to the rears when accelerating). I believe it also requires less wheelspin to activate compared to Continuous AWD.

    Another advantage is better integration with the ABS system. ABS and AWD work in almost opposite ways: AWD sends power away from the wheels that are spinning faster where as ABS tries to clamp down on the same wheels. With Continuous AWD, the VC lockup needs to be relaxed so that it doesn't kick in too soon and compete with ABS (it's passive so the unit never knows if you're braking or accelerating). With VTD, the system can tell if you are braking or accelerating and can delay or engage the power transfer as necessary.

    One last interesting quirk about Continuous AWD. My previous Forester had Continuous AWD and while it worked amazingly well on snow, it did have a tendency to "oscillate". When driving in very slippery conditions, the unit starts to lock, releases, locks, etc. and can be felt as a front-to-back transfer of power. I've read that both Active AWD and VTD have a far less tendency to do this oscillation.

    Hope that helps!

    Ken
  • kenskens Posts: 5,869
    Good question how the graphs would look like for the USDM turbos. Given that the USDM turbo has bigger displacement but a later peak torque, the slope of the first part of the torque curve (where the turbo is spooling) probably starts higher but has a slighlty lower slope. My guess is that initial throttle tip-in will be better with the USDM model.

    In any event, I think it's great that we can chose between two fantastic engines.

    Ken
  • sdufordsduford Posts: 577
    "My own test drives of both produced a pronounced preference for the H-6, but it is a shame that the great brakes and handling of the GT are not included. "

    Well I think the Outback handles amazingly well for such a tall and off-road capable wagon. I agree about the weak brakes though, that is my number one concern with the Outback. I cannot fathom why Subaru didn't put their best brakes on the XT and VDC. It puts in doubt their supposedly "security conscious" image. I'm hoping that putting better tires on it will improve the breaking distance.

    But even the GT is not that great under breaking. The Volvo S40 smokes it big time.
  • kenskens Posts: 5,869
    Braking distance is greatly influenced by the tires as well. I don't think the OB models have poor brakes at all. It's the higher profile all-season rubber that hampers braking distance. The current brakes on the OB are strong enough to lock the wheels up and activate ABS. It's the tire grip that determines how much braking force can be applied before the tires lock.

    That phenomemon is clearly shown with the GT. It has oversized brakes that have been reported to be very fade resistant, yet the all-season rubber hurts it against the S40 (which can be optioned with summer tires).

    Hey, you can't give all the GT goodies to the OB models! :-)

    Ken
  • Tom,
    Mine is the same way. I've tracked the difference on every tank but the very first and it's actually a bit more than 1 mpg high. I have no idea why it's this way.

    I am still loving the GT. Up to nearly 7100 miles now and it's all I could have wanted in a car.

    Now if I could just get my iPod to hook up to the stereo! I've been closely following the discussion over at legacyGT.com and hope Craig and centerpunch come up with a fix I can do myself. Doing in myself would mean that anyone can because I have absolutely no electronic/audio experience. All I know is that if you let the smoke out of the wires that's a bad thing and you can't get it to go back in. ;-)

    Cheers!
    -Ian
  • Craig,
    Let me know when you have some available I'll test them if you can help me (with lots of pics and detailed instructions) get it installed.

    Better yet would be something like what Dension has done with their iceLink product. I'd love to be able to control the iPod with the stereo controls and also avoid the "silence" CD.

    -Ian
  • c_hunterc_hunter Posts: 4,487
    Yeah, I agree with you, but I fear we have reached the end of the line without schematics or other engineering info about the radio. Finding the three audio pins in the 14-pin connector was a feat in itself, and I think centerpunch over on the LGT forum deserves a lot of credit for that. At this point, I see the remaining advances being how to hook up to the L/R audio lines and get everything integrated well.

    The circuit board will allow us to intercept the flat-flex cable (FFC) that runs from the CD changer to the radio. It basically just has two FFC connectors and some RCA cables. Unfortunately, it would require partial disassembly of the radio/HVAC unit to install the board, which makes it impractical for most people. Once you get the radio apart, plugging in the board is the easy part!

    All of the parts are available from DigiKey, but they require a custom board for integration and also, the pin spacing on the FFC connectors is so tight it precludes hand soldering. So, this has to be manufactured by a board shop.

    Craig
  • c_hunterc_hunter Posts: 4,487
    Any of the crew that are EEs, this is a good time to jump in and wow us with your expertise! So far, a bunch of hacker MEs have done all the work, so you can guess what that means!

    Craig
  • beanboybeanboy Posts: 442
    I'm still trying to figure out emission differences between the catless uppiped WRX STi and the catted uppipes of the Forester and Legacy. Both are considered Low Emission Vehicles (LEV), so there isn't even a "look-ahead" factor by Subaru in terms of meaning tougher standard emissions in the future. Anybody know how much 'dirtier' the STi is over the Legacy GT?

    Why did Subaru put in an expensive piece of equipment (probably at least $50 dollars at the factory level, which is huge on cars where every cent counts) on their volume turbo vehicles, when their top performing model meets the same emission standard and goes without?

    As you might have guessed, an STi uppipe will be going on the GT shortly after purchase... Just curious as to why Subaru did it in the first place.

    -B
  • c_hunterc_hunter Posts: 4,487
    I am not 100% sure about this, but it may have to do with the fact that the number of STi sold is paltry compared to the Legacy/Outback with the turbo motor. The emissions requirements may be based on a fleet average, I don't know.

    There's really not an equal substitute for having a cat close to the engine where the exhaust is hottest, that's why it's such a common approach.

    Craig
  • zman3zman3 Posts: 857
    geneshk:

    It's yours if you want it. If you haven't taken Rob up on his offer in message 4187 let me know how to contact you so we can arrange delivery of the coupon.

    Karl
  • Karl,
    Great!

    Please send me your email address to the one shown in my member profile, which is open to members. I will respond with shipping info and will be happy cover the cost.

    Much appreciated.
    Gene
  • ateixeiraateixeira Posts: 72,587
    So the AWD S40/V50s are here now? When I looked there were still FWD only.

    Go price a V50 T5 with AWD though, nearly $30 grand for starters. And keep in mind it's a compact.

    -juice
  • sdufordsduford Posts: 577
    The S40/V50 AWD have been available in Canada for a couple of months, but I know they were not expected to show up in the USA until the fall.

    Actually a well equipped V50 T5 AWD is pretty much exactly the same price as an Outback XT here in Canada, but it should really be compared to the Legacy, and I haven't checked those prices.

    But as I said, the Volvo is out of the running for me because of the lack of ground clearance. I was just comparing engine torque bands and braking ability, that's all. The Outback's breaks are amongst the worse on the market: only behemots like the Hummer have worse breaking distance. And while the tires play a part in that, it's not the whole story as most cars don't have very good OEM tires to begin with.
  • ateixeiraateixeira Posts: 72,587
    Gotcha.

    It's been a while since I drove it. I sampled the S40 T5 both with the manual and the auto. I thought the auto tranny lagged a lot and hesitated in shifting, something the Legacy GT I drove did not do. The Subie's tranny was so much better, that alone would decide it for me.

    The manual Volvo was a lot better, to me a requirement for the T5.

    Here is my Legacy GT full review:

    ateixeira "Town Hall Test Drive Team" May 20, 2004 10:42pm

    Here is my S40 T5 FWD review:

    ateixeira "Town Hall Test Drive Team" May 20, 2004 10:22pm

    The relevant portion from my T5 review:

    shifts were a little slow in full auto and manual mode. Plan ahead for shifts. The slush box also sapped some useful power from both models

    Just my opinion/experience, YMMV as they say.

    -juice
  • sdufordsduford Posts: 577
    I pretty much agree with your findings.

    I personally think both those cars are much better in manual. I find the auto trannies of both cars take too much away from the turbo engines.
  • ateixeiraateixeira Posts: 72,587
    I guess we didn't really test off-the-line acceleration in the GT auto, so perhaps I just didn't sample it in the situations where it would have bothered me.

    We did mostly rolling acceleration to merge onto the track, then track use, 2 laps. I went 3 times, once with a manual and twice with the auto.

    Took me about 3 days to wipe the smile off my face.

    -juice
  • sdufordsduford Posts: 577
    Ken, thanks for your explanation of the various AWD systems. I had been reading and re-reading all of Subaru's writing on it and found their message very confusing.

    They seem to be caught between a rock and a hard place. The VTD is obviously superior (if it wasn't, why would they bother with the complexity), but at the same time they try to say that the VC on the manuals is just as good.

    Your explanation makes a lot of sense. I guess the VC on the manuals is "good enough", but there are many advantages to the VTD. Although one could argue that the simplicity (hence reliability) of the VC is a big advantage.
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