V Spec Active Diff Control Algorithms? Aftermarket Ecu Control?

[Chris Wilson]

Not sure where top place this post, so please feel free to move it!

I am as much, or more, interested in chassis technology as engine technology, and I have often wondered what would be required to give meaningful aftermarket ecu control to an active rear diff in a 2 wheel drive car used on circuits? I have a 2 WD Skyline that I want to add an Skyline R34 V spec active diff to. Has anyone any links or info as to practical control of such a thing? Would a Motec M800 run it, or would I be looking at something totally different? Initially I would like to know how the Nissan ecu controls it, I know the 4WD cars have a 3 axis G sensor and steering angle input sensor, plus some brake input. Looking to reduce tight corner, off power understeer whilst retaining good corner exit traction and straight line traction. Thanks.

[bigmikespec]

Chris,

I have been thinking a similar thing, the A-LSD uses the Atessa pump to lock the diff. I am pretty sure it would use a PWM signal, I could set that up with my Vipec V88 as could you with your M800 (I would assume).

The only thing is, when do you lock it? You would have to work out when you want it locked, it might get complicated quickly. You would need some sensors (whether it be a similar set up to a GTR or something along the lines) to feed information into the ECU to "tell" it to lock.

Also, I have a R33 GTR Vspec A-LSD for sale it has better ratios than the R34.

Good luck,

Mike

[PM-R33]

It uses the ABS sensors on each wheel to tell it when to lock (along with a bunch of other things).

[sav man]

the gtr and gtst work differently afaik. the gtst works off slip %. the gtr system runs of attessa, so it uses gforces, wheel speed, and braking inputs.