Tom Blasing

A couple days ago I was watching one of the ESPN channels and the New York Auto Show was on (cool). They brought up the 05' Acura RL. Looked really good but the interior had what looked like a re-vamped BMW I-Drive system (yech) in it.

Anyway, while rep was talking to the tv show's host he hyped up a "new" feature with the RL to compliment the AWD system. He said that in a turn the outer wheels are over driven slightly faster than the inner ones to compensate for the radius distance between the two points (paraphrasing). Uhh....sorry that been done by just about every car manufacturer since (or even before) the 1950's. Take a look inside the rear differential in any modern RWD car and you'll see a ring and pinion gear that does just what this Acura rep said is "new".

agean

hmm, never heard of that before, but it does sound logical. i would assume a car with wheels spinning at the same rate would break traction much quicker through a turn

cali TL

What the acura system does is electronically apply extra torque to the outer rear wheel when you turn the steering wheel in the opposite direction, which generates yaw. A rear differential (like posi-trac i assume ur talking about), is merely split the torque 50/50 between the two rear wheels. The acura system can range from 100/0 (of available rear torque) and all the way back to 0/100. Its the equivilant of what a skyline can do with front to back torque, with left to right.

tlguy99

aww, you beet me to it. Think of a differential as a passive system. It takes the input and drives only one wheel directly. The other wheel is driven with a set of gears. This allows it to turn at a different rate of speed. The wheel speed is not actively increased as with the Acura system.

Shoofin

It's the Posi-traction of the old days...Like LSD (Limited Slip differential)these days..

tlguy99

LSD's and posi-traction are the same thing. Posi-traction is eatons version of the LSD.

Aegir

Here's a good video describing SH-AWD. It's a pretty impressive system:

http://www.world.honda.com/HDTV/news...01a/index.html

indoMFP

Man, that is awesome.... technology never ceases to amaze me...

MADCAT

Holy crap BATMAN...thats some complicated new AWD technology. Watch out Subraru and Audi...this looks very impressive...and its Honda's first crack at AWD....just wait till they learn more.....