internalaudit

Newbie here (owner of a 8th gen Accord) and after perusing a lot of car blogs / forums recently, it seems Acura offers a great balance between reliability, pricing, and one of the better AWD systems out there.

From its wiki, it seems that only the RL/RLX's SH-AWD was superior with the addition of Acceleration Device:
http://en.wikipedia.org/wiki/SH-AWD

SH-AWD write up on Honda's website:
http://www.honda.co.nz/technology/engine/sh-awd/

What kind of improvements are we seeing on the TLX's SH-AWD besides the introduction of Precision-All Wheel Steer (P-AWS)?

I'm kind of a cheapskate and was looking forward to the I4 but without the AWD, I might have to go for the V6.

Over at the Driveaccord forum, there doesn't seem to be too many complaints about the V6 relating to vibration and judder and hopefully none of that is found in the TLX, once released.

Treblig

Not sure anyone knows just yet.

vietxquangstah

iTrader: (7)

The other post says the new generation SH-AWD will be 25% lighter and has new torque vectoring control logic

Edward'TLS

^^^^^

How does that translate to actual vehicle performance in solid numbers ?

internalaudit

Hmmm. I wonder if the new SH-AWD will be as smart at the BMW's countersteering stability control + dynamic performance control:

http://blog.caranddriver.com/drift-b...soon-2014-ces/

Litt3

Nobody has driven it or reviewed it yet. The new DI injected V6 in my new MDX seems to be a very powerful engine, torquey.

We can only hope that the car is lighter, and with new SH-AWD will be very sporty.

I would not recommend making any decisions until you have actually test driven the new TLX with SH-AWD.

Also I think people should reserve their judgment on how it looks until they have actually seen the final production version in person.

George Knighton

The biggest disadvantage to SH-AWD has been that it only works throttle down.

So you could get through one or two corners in a carousel nicely, but might get into trouble in the third because you'd have to lift.

Once you'd done it a few times, you'd learn the fastest way...but you would always have this nagging feeling that it was not as quick as it could be because it only vectored throttle applied.

They have made a very big deal describing to us how the RLX SH-AWD is able to use the electric motor to apply negative drag on the inside wheel of a corner without using the AHA system.

So we know that with the RLX SH-AWD they're bragging that it works off throttle as well as throttle down.

My guess is that they've found some way to provide negative torque on the inside wheel of the TLX SH-AWD, or decided on a more aggressive application of the AHA system to do something equivalent; namely, an AHA system that works to do something on long U and carousel turns, not just the tighter autocross turns for which it works currently!

:-)

holografique

OMG, some actual common sense around here...am I dreaming?

KeithL

Agreed. The one thing I found disappointing with my 4G SH-AWD was that it was engaged very little. Even around turns if you were not into the throttle it was not doing anything for you.

Litt3

I'm hoping they will do some computer controlled active breaking on the inside wheels to to keep you on your 'line' as you go around corners with no throttle down.

fsttyms1

And what exactly were you hoping or wanting it to do?

keith7120

I totally agree Keith, I have had to really do some aggressive driving to get my display to show me the SH-AWD in action. I have driven it in the little snow we get here in Dallas and that was a plus. I'm beginning to think the V6 with P-AWS will be enough this go around for me. I wanted my current 2013 with SH-AWD simply because I felt it was more powerful than the base model more so than for the SH-AWD.

C8N

I've heard this comment a few times and I get confused. IMO, the whole point of torque vectoring is to cut the corners faster. If you don't have your foot on the throttle, how are you suppose to accomplish this?

However, as a safety feature, we still have VSA which I believe it will engage regardless of throttle or brake.

KeithL

Personally Acura should have redesigned it and beefed it up so that it could maybe do a 70/30 split all the time and not just under load. I got spoiled by the RWD in my M37S, loved that feel and the 40/60 plit of my Audi is great because you don't feel the car pulling(FWD) or pushing (RWD) the car just moves. I think Hyundai is looking to mimic Audi with it HTRAC, but time will tell. I want a proactive AWD system, not a reactive.

mylove4cars

VSA helps to stabilize the vehicle during cornering if the vehicle turns more or less than what was intended. It also assists in maintaining traction on slippery surfaces.

It does so by regulating engine output and selectively applying the brakes.

Other driving techniques will work as well like (Heel-Toe)

keith7120

I don't disagree with how torque vectoring works, nor I'm I disappointed in it. It "does" work as intended. I do view SH-AWD as a plus but again I test drove the base model and the SH-AWD and the power alone gained my interest. I came out of a 07 Type S. I didn't want to buy virtually the same power the type S had. So again I say, the power got my attention on the SH-AWD and then secondly, the SH-AWD is an added plus. Make sense?

internalaudit

Besides the A6's AWD system (and presumably many other Audi's), where else can I find pro-active AWD systems? I'm not talking about those brake-based active torque vectoring systems.

Thanks in advance, anyone.

KeithL

I believe Subaru?

mylove4cars

Located on either side of the hypoid gear that drives the rear axle, two identical Direct Electromagnetic Clutch systems control the amount of drive torque that reaches each rear wheel, and provide limited-slip differential function. An electric coil controls the pressure applied to a clutch, which slows the sun gear in a planetary gear set to modulate the torque that is sent to the wheel. The amount of torque transmitted to each rear wheel can vary continuously, between zero and 100 percent, depending on the conditions.

When cornering under deceleration (with the throttle closed), torque being applied to the outside rear wheel is varied to change the impact on the vehicles momentum from an inward yaw moment to an outward yaw moment, helping vehicle stability

Audi's AWD system today is still less effective.

012TL-GLM

My '12 SH-AWD seems to work all the time, regardless of how deep into the throttle I am. If the Go pedal is being applied and I'm turning the wheel I can see the power being applied on the SH-AWD display. How fast it gets out of a curve is scary. Acura achieved a perfect feeling of confidence and fear at the same time.

If the new system is the same logic and lost some weight that should translate into better trap times (I hope).

internalaudit

Probably not, even from one Subaru forum's thread, owners said the SH-AWD was superior.

https://www.toronto-subaru-club.com/...u-met-its.html

C8N

You sure you are quoting the right post?
My comment was merely for those that have said that they were disappointed with the SH-AWD because it did nothing when throttle was not applied. You seem to be pleased with the SH-AWD.

internalaudit

That's what I read on forums but gave Keith the benefit of the doubt as he has owned and driven both AWD systems and I have never owned an AWD but looking into it with the TLX.

http://torque-vectoring.belisso.com/

d1sturb3d119

iTrader: (1)

That's incorrect. SHAWD vector's engine braking during deceleration as well.

http://www.honda.co.nz/technology/engine/sh-awd/

Quoted from the honda website that states what the SHAWD system does under deceleration. There is no negative torque since torque vectoring is still occurring through engine braking but there is no negative torque being generated at the hub of the wheel. Negative torque is when an electric motor at the hub of the wheel regenerates power by converting kinect energy from the moving wheel to electrical energy acting as a motor to generate power while the car is braking.

When cornering under deceleration (with the throttle closed), torque being applied to the outside rear wheel is varied to change the impact on the vehicles momentum from an inward yaw moment to an outward yaw moment, helping vehicle stability.

If what you were saying is true these cars would be prone to massive lift off over-steer or under-steer especially in low traction conditions. Think about it.

The only thing that is new to the line up is that the RLX hybrid uses regenerative braking from the electric motor during cornering to charge the batteries. Besides that however the mechanical AWD system does distribute torque under deceleration as well which is why the handling is crisp both under throttle and deceleration.

The system employed by BMW and the older RL's are not as sophisticated because of the use of an acceleration device. All the system does is accelerate the wheel which is moving at a slower rate or not moving at all. Great for when you get stuck not for driving dynamics. The TL system is more advanced in that aspect.

It does not re-direct power to the wheel with most traction thereby limiting its overall efficiency.

winstrolvtec

It depends on how one defines proactive vs reactive and for the given situation but overall, I would still deem SH-AWD as an overall proactive system, where even the latest Audi gen VI is largely reactive. Still don't think that means too much because whether that makes one less or more effective will still largely depend on the strict circumstances and what the driver is looking for. Plus there is a lot to consider besides only the drive system in choosing a car.

SH is not without fault but it does work and work a lot based on my findings but, I do have a 6MT and maybe that's a bit different than the autos. As with any system, it will take an extreme for the system to operate to extreme capabilities but even in normal and only straight ahead driving anyone can see that the system is regularly and proactively transferring front to back and back to front, in the area of 90/10 to around 50/50 or so without having anything to do with turning, flooring it or a traction loss or slippage, etc.

Now you start bringing cornering and aggressive driving into it and we see up to 70% at the rear wheels and anywhere between 0-100% of that 70% or less diverted to a rear single wheel, also having nothing to due with a loss of traction or slippage, etc, just plain old throttle, steering position, etc. Generally associated with dry weather or pure handling vs poor road conditions.

That's why I say it's a proactive system, all systems in some form or another will react to slippage or loss but where I and many separate it is what the system can do or how it behaves when none of that occurs.

For examples, Audi did have an active differential option and may still have that as does BMW in very select few cars and variants, SUVs mainly, last I knew of, which more or less provide an active function for regular driving and dry handling very much like SH-AWD but only at the rear axle, not front to back and back to front and many makes now incorporate the brakes in more integrated sense to further enhance the ability (like Acura) or to simulate this effect in total but it's still not quite like having a dedicated differential or independent driven wheels via electric motors.

Nonetheless, it doesn't mean that others that are at a "fixed" 50/50 or 40/60 can't handle as well or better or are not perhaps better suited for other situations like slippery surfaces or start ups, for examples. Hard to narrow down because things like driver, weight, tires, etc all play a factor but I would still class the initial 90/10 distribution of SH as less effective in the contexts of slippery start ups, and although very limited, some handling instances.

As for the car feeling very front driven and FWD like, I think that is generally associated with the architecture and weight distribution but nonetheless, SH cars could benefit from, as others have stated, some ironing out or a bit more balanced starting distribution or perhaps adjustable in some capacity, like fuel mode, sport mode, etc for those split to few seconds of slippery start up and also during throttle lift off while turning. As with most systems though it is pretty well rounded and things like that are often a matter of give and take. To make those changes, I would bet that the minds at Acura would conclude that they would be sacrificing some reliability and fuel economy and probably why it is the way it is.

weather

You know, I said the exact same thing to my sales director over the phone today. I do like the SH-AWD for its cornering ability but I don't drive the TL in the rain or the snow so for me, I use the SH-AWD simply for its cornering ability. I am also not one of those super aggressive driver so maybe the P-AWS would suffice, with TECH, a V-6 and a bodykit. Now if I could only regain confidence in the brand....

holografique

I think you guys will be impressed with P-AWS. I've experienced SH-AWD once in a loaner TL while my old 3G TL was in service a couple years ago. And from what I remember, the P-AWS in my RLX feels very similar in handling and performance. I still get that same exhilaration when coming out of a tight corner and how well the car quickly corrects it's attitude.

I think it's clear that Acura's intention with P-AWS was to provide a wider audience of buyers with the "experience" of SH-AWD, without having to pay the premium. The result being the ability to provide a platform that all of the base models across their vehicles can offer and differentiate themselves from the competitors base models. It will be interesting to see if P-AWS ever makes it into the ILX base models. It sure would change the overall dynamic of that car.

Tonyware

All other things being equal... I am curious to know how the TLX will compare to this:

(click at your own risk)

2012 Acura TL small overlap IIHS crash test

d1sturb3d119

iTrader: (1)

To what? An excellent crash test when the car had been designed without the small overlap test in mind. I doubt acura is going to go back on how safe the car is. That's where a chunk of the cost of production goes to but everyone ignores.

Also the IS, BMW 3series and Merc only scored marginally.

ostrich

Hey, Weather, with all the heavy snow and blizzard out east lately, maybe you should just stick with SH-AWD!!!

JK.... LOL

Edward'TLS

After all, both Acura and Audi are implementing AWD on a FWD chassis, and therefore is limited by the amount of engine power going to the rear wheels.

As for the Infiniti AWD system, it drives and feels like a RWD because the system is able to do a front:rear power distribution ratio of 0:100%, due to it's AWD on RWD chassis design.

mylove4cars

Are you serious

Rocket_man

The TL got a 'Top Safety Pick' rating from the IIHS. Impressive for an older body design. The new Accord got a 'Top Safety Pick +' so I'm expecting the TLX, being designed for the small overlap test, will earn a 'Top Safety Pick +' I'm not worried.

The new 3-series got a 'Marginal' on the small overlap test.
The new IS has not been tested, but the previous model got a 'Poor' on the small overlap (ouch) and 'Acceptable' in two other areas.
The Q50 gets a 'Top Safety Pick +' even though it only scored 'Acceptable' on the small overlap.

So I'd expect this is one area where the TLX will shine.

CoquiTSX

Yes.

CoquiTSX

If it is, is @ a much higher price/cost. Subaru has it on all their models.

internalaudit

I have read that not all Subaru AWD are the same so you'll have to figure out which ones are better. They throw the jargon of symmetric blah blah but I don't care about that. I just want to know which AWD is most pro-active and so far the SH-AWD has had good reviews.

Hopefully, the one in the TLX will be an improvement over the current one, that's already received decent reviews/praises from journalist especially on wintry road conditions.

keith7120

Yes I was referring to your post in which you said you were confused. I am pleased with the SH-AWD drive but that was not the key of me buying that model, I bought this model simply for the feel of power over the base model more so than for the SH-AWD. I commented on earlier post in which I stated I had to drive more aggressively to get the benefit of SH-AWD, well atleast thats my perception.

d1sturb3d119

iTrader: (1)

What is your definition of FWD, RWD or AWD chassis. I see a lot of people saying this but I want to know what everyone really think's this is.

Also the Infinity feels like a RWD system because AWD is adapted into the the car and it does not have a continuous torque split like the Acura does making it's AWD system inferior overall. It can send 50% of the power to the front when needed but that still takes time and it's torque vectoring is brake actuated unlike the Acura. So in a bad situation I wouldn't mind the G37 cause I like to get sideways but I'd prefer the system that is on top of things all the time.

The chassis design has nothing to do with the way the car kicks the rear end out since that's down to torque split. Aside from that Honda built a car with neutral driving dynamics since no one is going to go racing professionally with a TL off the showroom floor. The transversely mounted engine and transmission make for a more balanced package which is not prone to understeer giving the user better control and if needed better tuning options if they want to rear to step out.

George Knighton

0_o

You're not doing it right!!!

Ha ha ha ha ha.....

I wouldn't exactly say that mine engaged very little, but I know what you mean.

George Knighton

I can't tell you how many times I have argued with Honda personnel that there is no such thing as engine "braking."

I understand what you quoted, and I understand your point.

It's a matter of perspective and detail.

The kind of drag that people are talking about, and the kind of VSA interference that people are talking about, is not what I am talking about.

I want the car to be smart enough to realize that you're not in trouble, and that you want to use an aggressive implementation of AHA with less mitigation of it by the VSA, when the car realizes that you're not "in trouble" as much as you do "mean business."

I'm sure I'm saying that badly, but if we talked it all through we'd be on the same side, I think, and we'd both want the car to be doing the same thing.