underground000 Posted February 8, 2009 Share Posted February 8, 2009 Not sure if repost but: There is 2 videos totaling 20 min., so if you have time to waste you can watch both This is showing the LGT awd with VCD turned on, how it can still have traction and compensate with wheel slipping There are also other Subies in this video It might take a while for the video to load since the quality is pretty good, press play then press pause till the red bar loads to almost finish if dont want video to stop half way Car on Rollers Test - Ice patch wheel slipage Legacy GT at 7:24 Forester 1:45 [ame=http://www.youtube.com/watch?v=ooQRxlChvMw]YouTube - Subaru AWD vs. competitors[/ame] LGT log climb/hill climb, with wheel loss traction Legacy GT at 2:18 Forester at turns 0:35, B 9 Tribeca 3:54, Outback wet road 5:00, B9 Wet road 5:30, Forester Hill climb 6:25, B9 Hill climb 7:36 [ame=http://www.youtube.com/watch?v=Q7dVFY5CxT0&feature=related]YouTube - Subaru AWD vs. Everyone Else[/ame] 5eat downshift rev match:) Powder coated wheels: completed:) Link to comment Share on other sites More sharing options...
Bbc84 Posted February 8, 2009 Share Posted February 8, 2009 repost Link to comment Share on other sites More sharing options...
f1anatic Posted February 8, 2009 Share Posted February 8, 2009 and not all that superior Link to comment Share on other sites More sharing options...
edkwon Posted February 14, 2009 Share Posted February 14, 2009 Glad you like your car but don't get all fanboyish. People tend to overuse words like 'superior' Link to comment Share on other sites More sharing options...
trademark Posted February 14, 2009 Share Posted February 14, 2009 thanks for the vids. I didn't see this if it was a repost.. Link to comment Share on other sites More sharing options...
Guest LGT-NY Posted February 14, 2009 Share Posted February 14, 2009 Pretty cool videos. You have to wonder though, since it was sponsored by Subaru how accurate it is. Link to comment Share on other sites More sharing options...
trademark Posted February 14, 2009 Share Posted February 14, 2009 why would honda sponsor something that didn't show their product is effective? someone had to sponsor it.. I dunno about the non-professional drivers.. I would liked to see some failures with the pros instead of soccer moms.. Link to comment Share on other sites More sharing options...
Guest LGT-NY Posted February 14, 2009 Share Posted February 14, 2009 I'm saying, if it was sponsored by a third party, it would be more reliable. Consumer Reports, etc. Link to comment Share on other sites More sharing options...
Bbc84 Posted February 14, 2009 Share Posted February 14, 2009 I want to see a non biased AWD review on all car manufs AWD offerings. I like my LGT, but I know its not the best AWD or superior AWD out there. Link to comment Share on other sites More sharing options...
IwannaSportSedan Posted February 15, 2009 Share Posted February 15, 2009 I want to see a non biased AWD review on all car manufs AWD offerings. I like my LGT, but I know its not the best AWD or superior AWD out there. What technologically is less than superior about it? Almost ALL other AWD cars use Haldex. Haldex does not use a center differential. ATTESSA is good, but it is front-wheel-assist, and normally 100% rear drive until slip occurs, or has a computer controlled torque bias. It is very good for performance, and slip assistance. Porsche AWD is similar, and rear biased, also very good. Bugatti Veyron has haldex, as well, but reversed, since it is mid-engined. Primarily RWD, with a computer controlled clutch for the front drivetrain. Lamborghini may use 3 differentials, I am not sure. Lately it is probably related to Quattro. Audi's Quattro is very good, and probably on par with the best of Subaru AWD. Three differentials, although the front and rear seem to be going toward open differentials, with brake force distribution channeling torque from side to side. Gaining traction by using the brakes seems kind of counter-intuitive. The new S4 with the supercharged V6 is said to be getting a torque vectoring rear differential, which could be very interesting. Subaru's AWD is symmetrical, doesn't torque steer, and has three differentials, and the better models have variable torque distribution on the center diff, and limited slip in the rear diff. The very best ones, from the S204 for instance, has a torsen limited slip front and rear, with driver controlled center diff. Exactly how does it get better than that? 4WD such as SUVs and Trucks sometimes have, is not a center differential, either. it is a gear-mesh transfer case, perhaps sometimes with a clutch pack to allow some slip, so that the drivetrain doesn't tear itself apart when turning the front wheels on pavement. Good for off-road, not so good on the road. I know first hand. CUVs usually have something similar to Haldex, and most other cars. Power take-off with a viscous coupling or clutch pack engaging the rear differential, sometimes with, sometimes without a limited slip differential in the whole system. Link to comment Share on other sites More sharing options...
Bbc84 Posted February 15, 2009 Share Posted February 15, 2009 What technologically is less than superior about it? Subaru's AWD is symmetrical, doesn't torque steer, and has three differentials, and the better models have variable torque distribution on the center diff, and limited slip in the rear diff. The very best ones, from the S204 for instance, has a torsen limited slip front and rear, with driver controlled center diff. Exactly how does it get better than that? Thing is the LGT does not have what the S204 and STI has. Thats why I say LGT is not the best or superior, I wasn't saying all Subaru AWD tech was bad, just what we got in the LGT could have been better. Not sure if we have the same AWD setup as the earlier WRX, but there are huge threads @ NASIOC about the Subaru 5MT AWD abilities. Majority of complaints seem to be the open front diff, and weak center diff that the 5MT WRX get vs what the STI's get. And the new AWD tech that other car manuf. are comming up with looks pretty interesting, like you mentioned the torque vectoring AWD systems Mitsu - with their AYC system Honda/Acura - with their SH-AWD BMW - with X drive is working with torque vectoring Saab- Turbo X has torque vectoring sys Link to comment Share on other sites More sharing options...
IwannaSportSedan Posted February 15, 2009 Share Posted February 15, 2009 The Spec B and 5EAT Legacies do have Variable Torque Distribution, which is similar to Auto-mode on DCCD, which isn't bad at all, and probably among the best AWD on the road. Front limited slip would be good, but it also creates heat and drag, and it probably isn't required for most day to day driving, and would only sap a little bit of power while the driving tasks wouldn't really take advantage. Only nearly-constant really hard performance driving, or soft-surface/slick driving would really bring out the advantage of a front limited slip. The 5MT Legacy GT probably does have a similar setup to the WRX 5-speed, but I have heard that the 5-speed was a bit more robust than previously, not exactly sure how. Having one myself, I can say it is pretty darn capable, and I haven't had a problem, at all, performance or reliability wise. The clutch is probably the weak link, really. One could compare the WRX or 5MT LGT drivetrain, and say that it is inferior to the 6MT and 5EAT Legacys and STI, but they also cost more. And most of those don't have Limited Slip front diffs. Maybe STI does, but I am not even positive on that, unless you go to an overseas Spec C or S204 or similar limited edition WRX STI. Some of that argument might have merit, of wanting better, but I think some of it might be a bit of bench racing mixed with wishful thinking. Mitsubishi's AWD systems are pretty good. They aren't longitudinal, though, which plays some havoc with front suspension and half-shaft geometry. But, like Subaru, have been tempered in WRC competition. SH-AWD is an interesting differential in the rear, it is basically a clutch-pack torque vectoring rear differential, but the same old PTO-driven rear-wheel-assist system, it doesn't have a center diff, and is front biased. BMW X-drive is interesting, but not all comments that I have seen are glowing. It seems more like ATTESSA, as front-assist on a RWD layout. Saab Turbo X is Haldex, with a computer controlled clutch pack between the PTO and rear drivetrain, so it has a bit of static rear torque bias, but it is normally front biased. Frankly, Saab 9^3 Turbo X would lose out to a black painted 09' Spec B in my book, and I would have ~5 thousand dollars left over for some kickin' 18x8 forged summer wheels, and trade the spec B OE wheels for 7-spoke WRX wheels with snow tires for the winter, a turbo-back exhaust system, and blacked out headlights with proper HID projector re-fit, to really take the Legacy up a notch, and really put the Saab out. That car would be cool enough... I would actually consider putting "2.5 Turbo S" on the right side of the rear decklid (Legacy on the left side, let all those Saab Turbo X owners know what smoked 'em ) G35X doesn't come with a 6-speed or the sport package, and a 335xi with comparable options checked off is much, much more expensive than $40k. In terms of AWD sedans with stick shift... the current Legacy is hard to beat anywhere NEAR it's price range, and Saab Turbo X doesn't beat it, except for maybe a cushier driver's seat. I mean, which would you choose, something like Arith's car, or the Saab? (thanks to Arith for sharing his car with us, over in the Official Obsidian Black Thread How many pictures are we allowed to put up? http://nyomi.arith.com.au/images/Nyomi_024.jpg http://nyomi.arith.com.au/images/Nyomi_025.jpg http://img2.netcarshow.com/Saab-Turbo_X_2008_800x600_wallpaper_03.jpg http://img2.netcarshow.com/Saab-Turbo_X_2008_800x600_wallpaper_05.jpg Link to comment Share on other sites More sharing options...
nka Posted February 15, 2009 Share Posted February 15, 2009 Cool, I love this thread ! Learning a lot now If I understand good, a automatic LGT will be better in snow than a manual LGT because of the center diff ? Link to comment Share on other sites More sharing options...
IwannaSportSedan Posted February 15, 2009 Share Posted February 15, 2009 The 5-speed automatic or the Spec B 6-speed manual might be better, by being able to transfer torque variably between the front and rear differentials, as needed. It is an advantage of degree, but that doesn't diminish the capabilities of the 5MT's symmetrical AWD. Variable Torque Distribution applies to Legacy 2.5 GT automatic, 3.0R models, and Tribeca, as well, all automatic, and the 2.5 GT Spec B with 6-speed manual. it has a 55% rear bias by default, and adjusts back or forward as needed, by computer control, with inputs like yaw, steering angle, throttle input (especially with Vehicle Dynamics Control), and wheel slip by comparing the ABS signal pulse rate of all 4 wheels in relation to each other. Theoretically, it can measure if a wheel on the front is slipping, but the rear wheels are not, it can channel more torque rearward, to take more advantage of that available traction, or vice versa, if the rear is slipping, but the front wheels are not. However, the 5-speed manual 2.5i and 2.5 GT, and similarly equipped Outbacks, Imprezas, and Foresters, even Bajas, all have Symmetrical AWD, with a fixed 50% front and rear torque bias. The Outback XTs and Legacy GTs have viscous rear limited slip differentials, WRXs and turbo Foresters and Bajas might also, I am not sure. 50% front and rear torque bias is still pretty darn good, and is fully capable AWD, it just isn't computer controlled variable torque, like the 5-speed automatic and 6-speed manual are capable of. If a wheel on one of the axles is slipping, the other axle has half of the engine's torque to work with, and the rear axle can divide the torque side to side, as well, with it's limited slip, rather than just using all the available torque to that axle to spin a loose tire. The older 4-speed automatic is still used in the non-turbo 2.5i models of Impreza, Forester, and Legacy, and possibly the Impreza GT, and Forester XT... It has a fixed-bias center differential, as well, IIRC, and some models are 90% front bias, some are more evenly split. I am not as familiar with the base model AWD system in the 4-speed Auto. I am sure there are other knowledgeable people here who can correct me if I am not remembering accurately. Better is a matter of degree, and all of the Subarus are pretty good, and any advantage over 2 wheel drive is still an advantage in traction. The high end versions just have more "bells and whistles", in terms of adaptability. Subaru systems are usually mechanically based, with real differentials, rather than just power-take-off being controlled by viscous coupling, or by clutch packs like most transverse-engine systems. Subarus use viscous couplings, or clutch packs, or even helical gears as limited slip devices to aid the differential function, not to replace the differential function, as Haldex does. They also generally don't try to use individual computer-controlled brake action to limit slip reactively across an open differential as some Audis, and Mercedes and others do, Subarus tend to use limited slip devices in at least one or two differentials, and rarely even all three, to prevent or avoid slip in the first place, as well as being engaged and working when slip occurs that can't be prevented. Subarus tend to leave the brakes to their deceleration duties. Link to comment Share on other sites More sharing options...
nka Posted February 15, 2009 Share Posted February 15, 2009 wow ! Could we add aftermarker DCCD (like neespeed ?) to electronicaly control the front/rear bias (manual? auto?) on the LGT 5MT or it's not just that missing ? Link to comment Share on other sites More sharing options...
Garandman Posted February 15, 2009 Share Posted February 15, 2009 The only really sophisticated AWD system Subaru sells is on the STi. The VTD system on our 06 3.0R is more neutral handling than the 50/50 system on the WRX, which always surprises people when they drive it, since they think like all Legacys it's a granny mobile. Who Dares Wins スバル Link to comment Share on other sites More sharing options...
IwannaSportSedan Posted February 15, 2009 Share Posted February 15, 2009 wow ! Could we add aftermarker DCCD (like neespeed ?) to electronicaly control the front/rear bias (manual? auto?) on the LGT 5MT or it's not just that missing ? The actual center differential component in the 5MT is different, dimensionally, than the 6MT and 5EAT transaxles. The 5MT doesn't have the facilities for the computer control of the center differential's bias setting devices. So, technically, no you can't just add DCCD to a 5MT. You *might* be able to add that to a 6MT Legacy GT Spec B, which shares the same basic transaxle as the STI, with computer-controlled bias. And that said, VVG, why do you say that the VTD AWD is any less sophisticated than the STI's system? The only thing that STI gains is a switch on the console, for the driver to over-ride the automatic computer controls... If an STI is always left on Auto DCCD setting, it is very little different than 3.0R Outbacks, Legacys, Tribeca, or 6MT Legacy Spec B. Link to comment Share on other sites More sharing options...
Guest LGT-NY Posted February 15, 2009 Share Posted February 15, 2009 Oh hi IWSS! /unsub Link to comment Share on other sites More sharing options...
f1anatic Posted February 15, 2009 Share Posted February 15, 2009 The Legacy GT line has a viscous (not torsen) center differential and with all models except spec B having a torsen rear - it really is ranking mid way on the scale. It is only better than the cars in the videos; not really the top offerings of Merc, Bimmer and Audi, Porsche and what not. For Subaru to match those, you need the VTD at the very least if not the STI technology - and it is funny that in your post you doubt that the US Spec STI may have front LSD. That is like required knowledge for Sport Sedan enthusiasts. Not to mention the reliance on viscous diffs. on the rear - which for years prevented the adding of vehicle stability control. Models that have it nowadays, including my 09 forester (and the Impreza) do not have a rear LSD anymore. The Torsen Spec B and the entire STI drivetrain is indeed progress by Subaru in the realm of manual gearboxes. But not the lowly GT drivetrain: something utterly paradoxal: better than quite a lot yet not superior in the least bit. For anyone who needs to brush up on Subaru AWD here is the official brochure from Subaru Australia explaining what each does, with the relative features + a little history. And that suggestion goes to everyone, including IWSS ! http://home.comcast.net/~a6n6d6y/andy/Subaru%20AWD.pdf Even the 4EAT is a more advanced system the the 5MT. This is for "system sophistication", not for "getting the most out of your F-18 Hornet like horsepower" 5MT < 6MT < 4EAT < 5EAT < DCCD Link to comment Share on other sites More sharing options...
nka Posted February 15, 2009 Share Posted February 15, 2009 that explain why [4,5]EAT have more difficulty to do drift sideway, since the system is better at keeping the car on track. That also explain to me why some subaru stuck in snow have only 3 wheels spining (2 rear, one in the front), and the one in the front isn't the one on asphalt ! Link to comment Share on other sites More sharing options...
Garandman Posted February 15, 2009 Share Posted February 15, 2009 // And that said, VVG, why do you say that the VTD AWD is any less sophisticated than the STI's system? The only thing that STI gains is a switch on the console, for the driver to over-ride the automatic computer controls... If an STI is always left on Auto DCCD setting, it is very little different than 3.0R Outbacks, Legacys, Tribeca, or 6MT Legacy Spec B. Oh, in addition to the DCCD control itself? The TORSEN rear differential? The planetary geared center differential? The helical (mechanical) front differential? Who Dares Wins スバル Link to comment Share on other sites More sharing options...
IwannaSportSedan Posted February 15, 2009 Share Posted February 15, 2009 Again, Auto DCCD is the same as VTD. The center diff is virtually the same, the STI just has an over-ride setting, if the driver ever wants to use it. The Spec B also has the rear Torsen Diff, and the GT 5EAT and 5MT, outbacks, 3.0R 5EATs, Tribecas, etc... above the 2.5i level all have viscous limited slips. As for a helical front differential, that is what TORSEN is, essentially. The only significant difference is if it is made by Torsen, with their trademark, or whether it is built by someone else. Kind of like not all poly-styrene expanded foam can be called Styrofoam, it is all the same stuff, not all of it has the trademark name. The regular STI has a limited slip in the front differential, then that would be the other (of two, counting the console switch override) difference between STI and the Spec B, drivetrain wise. And theoretically someone with some $$, could swap the parts straight across. The transaxles are the same unit, the STI having the slight bit more feature content of the front LSD, and the switch on the console. It is even a bit frustrating how close the Spec B is to the WRX STI yet is just very slightly shy of, and how with just a slight bit more... the switch, the front LSD, a slightly hotter turbo and tune, Brembo brakes, and the Spec B would be every inch what the STI is, mechanically. As we know, all of those parts can pretty much be added to the Legacy straight across. BTW, Subaru does it's usual pathetic job of marketing for the Legacy, on the Spec B's features and specs page on their new website, and mentions virtually nothing about the AWD tech that Spec B has. Here's hoping they do a better job of marketing for the '10 Legacy. Link to comment Share on other sites More sharing options...
Garandman Posted February 16, 2009 Share Posted February 16, 2009 So, in summary, the Spec B is the same, only different. That and the 62hp..... Who Dares Wins スバル Link to comment Share on other sites More sharing options...
camber Posted February 16, 2009 Share Posted February 16, 2009 It's weird how viscous center diffs don't get any respect. Do you know that they are still used in the WRC by some teams? It took a very long time and lots of money, to develop electronic control systems that were better(or made them better) then vicous in only certain circumstances. I'm not even sure that this technology has made its way down to mass produced cars yet. Link to comment Share on other sites More sharing options...
IwannaSportSedan Posted February 16, 2009 Share Posted February 16, 2009 So, in summary, the Spec B is the same, only different. That and the 62hp..... We're talking AWD, I was just making a wishful thinking statement about Spec B being closer to STI... I wish it were. We aren't comparing engines. The engines aren't that far off, either. A slight turbo difference and ECU tune is ALL there is there. Mostly, I was saying, that some of the things you list as being different, aren't. It is different, but not as MUCH different as you asserted, and the real-world effects are probably quite a small number of degrees. You said the only sophisticated AWD system was the STI, I contend the differences are smaller than you think, and other well-equipped Subarus have very sophisticated AWD systems, even if they aren't absolutely identical to STI's system. Spec B, 3.0R and other 5EAT equipped Subarus are most definitely not slouches, in the AWD department. Nor are 5MT symmetrical cars. Link to comment Share on other sites More sharing options...
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