TampaRLX-SH

I was watching Autoline Detroit this morning and there was a featue on Saab. Apparently Saab is introducing their attempt to copy of the RL's SHAWD to be called 'Crosswheel Drive' or XWD.

From Saab.com:

Driver in Focus with Saab XWD

Intelligent Saab XWD for superb handling and roadholding
Rear eLSD gives torque transfer up to 40% between wheels
280 hp 2.8 V6 Turbo with twin-scroll turbocharger, variable valve timing
Sports tuned chassis optimizes all-wheel-drive benefits

The Saab Turbo X adds a new dimension in chassis control to Saab's unrivalled experience in turbocharging. It is the result of a development program that leverages the full potential of Saab's innovative XWD system, with the car's sports tuned suspension, brakes and electronic control systems all aligned to meet a single need: driving satisfaction.

Saab XWD is an active all-wheel-drive system designed to optimize vehicle handling and stability. Its sophisticated electronic control allows fine balancing of drive torque, not only between the two axles but also between the rear wheels. In effect, this stretches the performance envelope of the chassis, for example, raising the threshold at which ESP throttle and braking interventions are triggered. The result is closer driver involvement through 'positive force' chassis control.

The driving benefits of the XWD system are best appreciated out on the open road. Data from the ABS/ESP sensors - measuring wheel speed, yaw rate and steering angle - is utilized by the Saab XWD control module. Rear drive is instantly applied to balance oversteer and understeer characteristics, improving stability and roadholding.

Driver control is taken a step further on the Turbo X by the eLSD, the first application of an electronically-controlled, rear limited slip differential in this segment of the market. It uses inputs from the rear wheel speed sensors and can transfer up to 40% of torque between the drive shafts, to whichever wheel has more grip. When cornering hard, this yaw damping effect helps the rear of the car more closely follow the direction of the front wheels.

Not as sophisticated as SHAWD, but still...considering how many poo poo the need for SHAWD, there seems to be several manufacturers eager to copy it. So far we expect BMW, Audi, now Saab? Any others?

Imitation is a sincere form of flattery, indeed.

Chas2

So that makes SAAB, BMW and Audi!

csmeance

but acura's system (to my knowledge) is the most advanced one, it can do up to 80@ to the rears and 70 between each rear wheel. The article quoted only 40 for saab....

neuronbob

As usual, Honda leads and others follow.

SH-AWD FTW!

Chas2

Actually, it depends on the vehicle. In the RL, at least the 2006 version, 70% can go to the rear, and that 70% can all go to one wheel if required.

In the MDX, the balance is different. In a towing or heavy load situation, 70% can go to the rear, but in a turning situation, the rear torque will be limited to 50%, and that total 50% can be directed to one wheel or the other.

The RDX has a slightly different balance, but is closer to the MDX...

I am being purpose vague here because there are so many differing descriptions of the system between brochures, acuranews.com, www.acura.com, and as well as possible programming changes between model years. nFor example, the RL in 05 and 06 seems to be set to a range of 70-30 FR to 30-70, while 2007, and 2008 seem to be 80-20 to 20-80.

Acura has been less than stellar in its configuration control between documents.

kirbyflorida

I took an on ramp yesterday that still amazes me a day later, this system really works.
When someone hits the limit of the system on a second gear smooth transition, let me know, just amazing.

Try it guys, it is a thrill, be safe.

lumpulus

Yeah, I feel it every day on the way home on a certain Massachusetts interchange.

gavine

There is no mention in the Saab article about accelerating the outside rear wheel. Torque is one thing, but to speed-up that wheel makes most of the difference. Theirs might help in slippery situations but for dry road handling, SH-AWD with the acceleration gear still sounds like a better system.

black label

Front to Rear bias depends on the year. SHAWD can transfer 100% of rear wheel power to the outside rear wheel and accelerate it up to 5% over the inside rear wheel speed(up to 5% on the RL only, 1.7% on all other SHAWD systems).

TampaRLX-SH

Agreed gavine. The copies have yet to achieve SHAWD's sophistication. Black Label defines it more specifically.

black label

95/93 or Rt1/95? I love both. If you're behind a red CL type S with Bruins plates, try to keep up