our Torsen diff from our viscous coupling
and the difference between eLSDs and active differentials, we can appreciate the benefits to the kind of cars we like. While getting a bit depressed that more and more manufacturers are choosing software rather than hardware when it comes to limited-slip differentials.
VW has been testing active diffs for next Golf
The modern way is to get the car's ESP brain to nip individual brakes to help it round corners instead of redirecting the torque mechanically. Not because it's better (it isn't) but because it's cheaper. But there is good news on that front. Volkswagen has been one of the worst offenders for palming us off with electronic brake intervention and calling it limited-slip diff under the EDS and XDS brand names.
Now it's saying the next Golf GTI will be available with a proper mechanical limited-slip diff, and an electronically controlled one at that.
That would make it the first production front-wheel-drive car in the world to get one.
No cliche left unturned in quest for traction
Even better, it won't be restricted to the Golf. The technology has been developed for what VW internally calls the MQB platform. That will underpin everything from Polo to Passat, not mention small and medium Audis, Seats and Skodas, meaning theoretically they can all use the so-called VAQ tech.
VW wouldn't expand on its use within the group, but did say it would likely be an option on the next generation Golf GTI, the standard version of which will be revealed later this year, as well as the diesel GTD.
This is how good it will be. In a comparison between two racing-prepped Siroccos at the Nurburgring - one with, one without - the VAQ-equipped car averaged 8.5-second faster times. That's because instead of braking away power in the bends to help the car round, it redirects it to the outside wheel. And because it's taking information from throttle position, steering angle and other sources, it should be able to deliver power without the compromises of a passive system on, say, the Renault Megane 265.
Essential 'ring lap stats show extra speed
If it was good as an excellent GKN front-drive LSD we tried on a Mini Cooper S recently, it could offer nicely controllable oversteer into the bargain.
The only drawback will be price. It's an expensive business integrating this tech and the standard Golf GTI isn't cheap. But if it creates the ultimate-handling hot hatch, maybe we won't mind paying.