Subaru XV Crosstrek HYBRID to be announced at NYC auto show

Those two were asymmetrical in the past, and I don't see them changing that soon. Purist will say a symmetrical system gives better performance, but I have never needed more than FWD for my winter driving.​

 

Thanks, I have mainly driven jeeps for off road, and have driven some awd audis for traction performance. I completely agree with anyone that thinks I am ignorant when it comes to awd Subarus. I just have one friend with one, and she swapped her vw for it with her parents, so she would have room for her dogs. Then people started telling her it was a lesbian car. Oh well.


Let's clean sheet this. I don't think you can do a better off road awd system than the jeep rocktrak. But first thing I think you ditch on the set up is the fully boxed body on frame, and substitute unibody - gets rid of ruggedness but in a tall car like the crosstrek, c-max etc, you want that lower weight and improve ride comfort. It is a 50/50 split of power in 4H, which may be what the subaru is going for. I guess the suba doesn't need to crawl so it doesn't need 4L, and they don't want the drivers to have to decide so there is no 2H. I would say 2H would give you superiour city fuel economy though, so thinking about this in a 2013 way with slipping wheel sensors and electric motors, a eAWD could be technically superior if money is not a problem.

I found the description of the escape 4wd system interesting
Features, Features, and More Features!

It seems like having an electric axle would be simpler.

For that approach the original system proposed for the porsche 918 seems the best. This provides rear drive with a generator, to take some of the power. Then each front wheel has its own independent drive motor. The car is a plug in and uses a double clutch transmission though. Simplying toward a less expensive system, let's say front drive with a generator. The crosstrek already is cvt, which means the hsd transaxle from a camry could be used to replace the entire engine and transmission. A mg3 could be affixed to the rear axle, and a bigger battery used. That wyould allow for most efficient 2H when selected, but symetrical 4H with electric power from the battery and mg1 fuelling the rear mg3. This describes mostly the lexus rxh system. Note the porsche goes plug in not just because it wants electric driving, the big battery provides that extra awd torque. I believe the production 918 loses the independant front motors and only uses 1. I would expect under heavy acceleration you would want more power going to the rear wheels than the front to avoid torque steer, on highway cruise all the power going through the hsd to the front for efficiency.

The big question is what it would cost subaru, and my guess is more than they wanted. It would not cost toyota or ford much at all to add the option on the prius phv or c-max energi. Such a system may not improve max hp, but would improve usable hp and acceleration as well as safe speeds to turn in wet/muddy/snowy conditions. Safest in the snow is ofcourse tires that add rolling resistance though, my jeep trail trips required my friend to put on the knoby tires. The main problem with the system in the Rxh is cost, but I expect the next toyota system to drop cost.

 

what you are suggesting is same system as in RX450h... it is not that costly due e-awd, upgrade for AWD vs FWD for RX is the same as for e-AWD vs FWD, or $1500.

"Problem" with that setup is that hybrid system itself is expensive - low volume V6 hybrid, not e-awd...

As to Subaru, they will never have that kind of AWD, reason they use full time AWD is due to stability under all situations. This is main point of Subaru - full time AWD.

I would expect upcoming NX300h to have e-awd like RXh, just will smaller powertrain and less cost.

 

Yes I was not suggesting that it was the eAWD that made it expensive, I said plain out that it toyota was selling the system as expensive and anouther variant need not be, but it is likely toyota does not want to display that first in a subaru before its own car.

I have no idea why an electronic system could not work as well if not better than a mechanical 4wd system. Even jeep is going for electrical control of their mechanical system.

I have no speculation on what toyota will initially launch a new system.

 

Subaru and Toyota are not same company... Toyota owns about 16% of Subaru and doesnt control it... Toyota would love to sell Subaru its HSD but Subaru as many Japanese companies is fiercely independent.

The difference between full time AWD and part time e-AWD is huge. Since Subaru's niche and reason their sales are constantly going up, is full time AWD, putting e-AWD would be like Ferrari developing FWD car.

Maybe one day they will do it pressed by regulations, but right now, their sole reason of existence is full time awd. I am not sure why are you pointing Jeep all the time, Subaru and Jeep are nothing alike.

 

What are you arguing with me about then. You were acting as if toyota was subarus parent. Just get over it. The price is not right. Nissan built their own system not because they wanted to be independent but thought toyota was charging it too much money.

 

Conversion losses and cost. The rear wheels are essentially a serial hybrid. Since the current eAWD system only operates periodically, it can rely on the battery to buffer most of its power needs. When going full time driving of the rear, the MG1 will likely have to be upgraded to be able to supply the rear MG with the electricity it needs to to be spinning for the entire drive. The current system is about a 1mpg loss. Better than the losses of a mechanical asymmetrical system which has AWD parts spinning even when they aren't needed. But these are systems that may not actually see use in day to day driving. If it is going to be used all the time driving the rear wheels, then the mechanical losses become less parasitic. In addition to the CVT, Subaru has also reduced the losses of their AWD system in the newer models.

Simply, an electric AWD may lose all its advantages when it has to run all the time versus running occasionally, or not at all, during a drive.

Does Subaru have a tow rating on this car? That might be another reason not to use HSD.

 

I respectfully disagree. We took our forester on the beach, Fire island, soft and deep sand. We had to air down, but never got stuck. No road.

 

doh, I should have made clear other than cost.

You have convinced me that the current toyota implementation is less than ideal, but we know they have a new one coming. Let's dispense with some marketing speak, versus real needs though. Two reasons subaru claims to need to be spinning the whole time is What if? and torque steer. Certainly the new escape system that updates every 16 ms coupled with electric motors would be fast enough to move power in the what if I slip situation. Traction control must work well quickly, so the computational overhead is mostly with us. With mechanical clutch packs and differentials this was more of a problem. Many auto makers now use their electric power steering to correct partially for torque steer, and the car could route the power to the rear wheels in these high acceleration situations.

Then the question is how much power is needed and how many losses will occur. Off roading its most likely 50%, but max power is not needed. For on the road audi has done a lot of work with its quatro system, and has found a 40:60 split to be most effective, but on the new system allows up to 85% to go to the rear wheels. Say we have a 150 hp vehicle like the crosstrek we would likely be happy with 90 hp going to the rear wheels, and the cases where audi uses 85%, 105hp max is probably fine. You could A put in a 7kwh battery - like in the ford energis - and provide all that power, or slightly revise the hsd to provide the electrical power. Heretical mode already uses mg2 as a generator, which may mean no changes to hsd may be necessary, but they may improve system performance. I would not think you would need those 90 hp for more than 10 seconds at a burst, perhaps just a slightly larger battery. What should this do to fuel economy in 40:60 mode? I would assume about a 15% electrical loss on that 60%. That might drop you in a 40 mpg vehicle to 37 mpg (some is in the electrical split now), if you don't hit the eco button and stay in mainly fwd unless you slip or heavily accelerate. The question then is does the hybrid fuel economy trump what the losses? Everything I have seen says it will. I'm curious to see what the EPA charge sustain numbers are for the misubishi phev, which uses pure serial mode in the city tests.

In higher powered applications with heavy loads on the rear wheels, a different rwd hybrid system, with independent motors on each front wheel may be a better hybrid eAwd system. Hopefully Toyota and Ford working together will come up with something good on their joint development. On that vehicle, in fuel economy mode most of the power will go mechanically to the rear wheels, until they slip. Electric torque on the front wheels will help get large loads moving, and allow for engine downsizing.

In my mind they already have it a compromise of cvt for awd for fuel economy. They have a loyal group that likes what they do.

1500 on this car on the non-hybrid. That is significantly less than the lexus Rxh.

 

​

Depends on which Rxh, the 2WD has a rating of 0.
An HSD Crosstrek should maintain the 1500.

Some do go off road. In the couple head to head reviews I've read, the Escape hybrid, with mechanical AWD, was considered to be more capable off road than the Highlander hybrid. That might be more to the platform and suspension, but why re-invent the wheel from Subaru's perspective. AWD HSD will need some work to meet their needs, and they just came out with a more efficient AWD drive train. The redesigned Impreza did have some impressive fuel economy improvements with it and the CVT.

Going with a larger battery negates some of the space and weight saving of the electric AWD system.

I can see how an electrical system can be better. Specially in flexibility in choosing FWD or AWD. I don't think Subaru wants to go that route though in order not to muddle their marketing. Their system seems to be around the 60/40 split(depends on transmission and AWD system).

Ultimately it is the cost. The more parts used from the the non-hybrid, the more resources saved. An eAWD would likely improve the hybrid Subaru mpg over the gas model, but their market is already aware of the economy hit from an AWD system.

Why did Toyota go with eAWD? Design exercise with more new tech for marketing to point to, or did the HSD layout prevent the existing AWD drivetrain from being used? HSD was originally designed for FWD while Ford was designing their initial system for a FWD and AWD vehicle.

 

I just didn't the thing looked like a good hybrid. Agree the highlander hybrid eAWD system would need redesign. What I was saying was if you want the gas savings, you can definitely get the AWD performance from a motor based system.

The big advantage of a motor type system is response to shift power between the wheels. Replace the nimh in a prius with lithium the same size and weight, and you get enough power without changing size and weight, but you still take the hybrid hit. Prius phv, didn't get a mileage hit, but volume decreased, and I would think you want a spare tire if you might leave paved roads.

There simple system is 50/50, but the WRX is 41/59, closely resembling the quatro systems 40/60. Both systems can channel most of the power to the front or rear, unlike the highlander mechanical or eAWD. Agree that if people liked the eAWD system better, that may hurt their marketing.

Yep, that's where I come down, and the reason I am replying is that the hybrid didn't appear to improve their gas mileage much.

Ford was able to mate a system similar to hsd to their AWD system, but it took a 3 mpg hit versus fwd. For those paying extra for the hybrid, that AWD hit hurt sales. Sales of the option were low enough that ford didn't release AWD as an option on the c-max, although they could add it later. Toyota likely went through more of a development effort to get its eAWD system in place and not take the mpg hit. From the system as described it is probably not as capable as the ford system, but people may be buying eAWD in the RXh as more of a check box than real need to go off road. You would think that if someone knew how to drive it though it would do well in mud and snow, I've taken fwd and rwd into both.

 

A delay in shifting power doesn't appear to be a disadvantage of Subaru's system.

Being a conversion, wouldn't lithium almost be a must to have the least impact on usable space. I guess without the mechanical AWD system in place there would be a place for the battery.

Another train of thought, is Toyota's eAWD system mated to an engine smaller than a V6? Could there be a floor of minimum ICE output for reliable operation of the eAWD system? Not that the system would break, but reliable in providing a constant level of performance. In other words, would power output at the rear, or both front and rear, drop when the SOC was low and the engine smaller?

If that's the case, an atkinson/miller cycle engine of the 2L may not be able to power the system for sustained time. Yes, a larger battery pack would buffer it, but you don't want negative press from people that do hit the limit and experience turtle mode.

Subaru has 3 to 4 different systems with tweaks based on models. The Forester had a different torque split than the cars.

I was commenting more on how I don't think Subaru would offer an asymmetrical system. An eAWD system may be superior, but if had a 100% FWD mode, that would counter their symmetrical system is better marketing.

Meh, it's a mild assist system. I don't hold much hope. However, the Impreza did gain 8mpg with the redesign, and they have working with hybrid concepts for ten years. So I'm willing to wait for the official numbers. Including price. Small gains can be balanced by small price.

Toyota also had more room to pay back R&D with a Lexus price tag. I agree on the check box thing. It seems more important to get for those that want to tow than for traction improvement.

 

That is because it is on at all times, if you are going to be going for the most efficiency, latency is an issue. If its at 45/55, and a rear tire slips, 45% is already going to the front. If a car is at 100%/0% for efficiency, and a front tire slips, but you can drop 85% power to the rear quickly its just as good. When a subaru or a jeep looses traction there is a delay in the power shifts, but there is already power going to the wheels with traction.

I have no idea what is going in or out. camry and fusion are both designed as both, camry has the bigger battery and more trunk space. Out of the midsized cars the fusion IMHO is the prettiest, but it certainly didn't do the best packaging. But yes lithium seems to be the best trade off today all things being equal.

An eAWD vehicle will likely be more demanding than a hsd fwd on the battery, especially if wheels are slipping. That's why I commented it may be best with a bigger battery. I do notice some loss of power when SOC is low on the highway with hills and air conditioning. That simply is a matter of managing the SOC. The prius is 98hp engine, and 36 hp battery when in the sweet spot. If you are going for efficiency and have a hybrid already eAWD seems the way to go. AWD cars though do consume extra power, and that is part of the design decission.

When toyota got to the gen II turtle mode disapeared 98 hp is plenty to go up pikes peak and recharge the battery, its all a matter of managing the SOC. The bigger battery can add hp though, say it was 50 hp instead, the eAWD version gets a boost of hp, and only pays the ineffieincy hit when it uses it. There is also a time delay between acceleration and engine revs that goes away with electric power.

I kind of find their symenetrical stuff gobbly gook in 2013. Different situations require different asymetries, and dynamically managing them seems to make sense. For most situations a rear bias is better for handling, but even bmw is looking to go fwd for efficiency. A mainly FWD mode would switch power to the rear wheels when they slipped, but provide better fuel economy, perhaps it would vector power there under hard acceleration to counter torque steer, but I've tried in my prius and can't get enough power for good torque steer Definitely you would want a mode that did something like a 40/60 split mode for snow, mud, or off road. Then again maybe we are too lazy to hit the switch, and want to spend extra gas on dry highways.

agree completely.

Mercedes just released some marketing that said customers in the north east and midwest were starting to pay more for 4wd. I think the system can be improved quite a bit, and costs brought down. If you can get hybrid and awd + 30 hp in a camry for $5K more than the gas only that isn't a bad value proposition.

 

Ahh.

That is the crux of Subaru's decision here. They are starting with an AWD system and adding an hybrid. Perhaps they would have chosen eAWD for ground up hybrid, but they aren't the big player Toyota is with a narrower market. So they are sticking with what they know and what their costumers want. Not offering a non AWD here eliminates the comparison the Escape had between drivetrains' fuel economy.

My google-fu has failed. Was there an increase in the battery's power/output between the generations?

Toyota might have conquered turtle mode, but this is Subaru. They have customers more likely to be taking their cars on rougher terrain than Toyota eAWD owners. Toyota even states the Highlander/RX aren't intended for off road use. So a eAWD Subaru will likely see more use than a system that is only intended in augmenting traction on road.

The Otto cycle 2L in the Impreza produces about 75% of the power of the HiHy V6. Is that enough to power the rear motor during extended use? Will an Atkinson cycle engine have enough? A large battery will help, but that needs to balanced with use of space.

Cost is a major factor for their decision for hybrid and AWD system. There is also the risk assessment. The AWD system is tested and proven. Leaving it in place eliminates the variables of potentionally going wrong of introducing an eAWD system along with a hybrid system. Honda trashed their hybrid reputation with a simpler hybrid system. Subaru is just being conservative with their first hybrid offering.

Land Rover, Jeep, and Ford all offer an AWD/4WD system that allows user selection based on terrain and situation. That might become the norm, and eAWD would make it implement since it would mostly be software that changes.

And I think people are too lazy and/or foolish to simply get a set of winter tires. There is a cost to swapping sets twice a year, but they are paying a cost everytime they drive with an AWD/4WD system.

 

We own a 15 year old Subaru that wears Ice-x winter tyres. The car is really only used for hauling duties and during nasty winter days. The other 98% of the time we drive our Prii.

It will be quite a feat for Subaru to come up with a single car that comes close to matching the price and utility of what we have now.

 

The key to turtle mode is head room of the ice to charge/deplete the battery. Battery changed between gen I and gen II, but I can't quickly find gen I kw or kwh, gen II was 25 kw and 1.3kwh, gen III upped power to 27kw but kept the same energy. The bigger changes from gen I to gen II is less power was needed to do the same acceleration and ice improved from 70 hp to 76 hp, while the battery could be recharged fasster from the ice or braking. This resulted in much better ability to maintain SOC, and better power when battery depleted. Gen III upped ice power to 98 hp. A gen III prius with a low SOC battery will likely out accelerate a high SOC gen I, and will be able to recharge the battery fairly easily. Thus turtle is gone because the ice power is not greatly undersized. The volt has an undersized ice and needs to maintain a higher SOC just in case.

148 hp seems quite low for a AWD vehicle.

I would say hsd + eAWD likely would need less hp than this crosstrek hybrid system, but agreed, that is not likely a great power to weight ratio.

I see subaru following honda's hybrid system. Its 2013, I just expected something better. You could mate an hsd type system to the awd system like the escape did. I just see kludge in the IMA to cvt in a low powered AWD.

Yep, and Ford seems to have chosen to act better if you choose wrong and forget to hit the proper button. ABS systems seem to get implemented with traction control to avoid many situations where AWD was needed before, but pushing cars past their capabilities will always be a problem.

That is a problem for the trade off.

 

In CA, CHP requires cars going up the Sierra to chain up during snow storms. Knowing how lazy Americans are, they prefer driving 4wd/awd cars than to put on winter tires and/or chains.

 

The Audi A3 has 200hp. Being around 500lbs heavier, its power to weight ratio is a little lower than the Subaru.

Other companies commonly only offer AWD or 4WD with the larger engine option. This might have perpetuated the notion that such systems needed more power while not necessarily being true.

For clarification, we have been using power when it is really torque that is being distributed among the 4 wheels. In most modern engines, that tends to be a value close to the horse power. It's 145ft-lbs for the subaru, and around 200 for the A3 and Highlander engines.

There is still some potential in an IMA type system. If priced right, a modest economy improvement can be compound by greater sales. Hyundai seems to be having some success with their hybrid. Subaru has been pursuing this for about a decade. It's 2013, there are only two companies selling non-plug in full hybrids at this time, and the hybrid offerings only expanded to more than 3 companies only recently.

The hybrid system in the Escape is laid out differently than HSD. The MG2 is mounted transversely, parallel to the drive shaft for the rear wheels. The time needed to get an HSD unit mated up to their AWD, or developing an eAWD for their needs, isn't something Subaru wants to invest it. Perhaps they do, and the assist system is ready to go now.

Again, I didn't see the bolded part until the quote appeared in the reply box. Anyone else have this issue?
I nothing say about this beyond that.

 

Absolutely, I always had chains in my car going up to tahoe when I lived in the bay area. Its a pain to put them on, but snow tires wouldn't cut it with my vehicle.

On a eAWD system it would be hitting a button. Its not like having to put on chains.

 

Let's look at specs that Subaru was evolving for a decade.
2014 Subaru XV Crosstrek Hybrid, WRX concept thrill NY - MSN Autos

If you get the epa, over 150,000 miles you might save 400 gallons of gas.

The Hyundai and VW hybrid systems are different. They decided to use a more powerful flywheel electric motor that can power the car without the engine. They get significantly better fuel economy, at least on epa compared to their non-hybrid versions. I can't imagine making the motor 27 hp like vw, and adding another clutch would change costs much.

Yep it takes more work, but I don't think this implementation is very good for 2013.