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At the risk of firing this thread off on a tangent - does the R32 V-spec have an active diff? I always assumed it had, but in the absense of hydraulic lines I now doubt it somewhat.

From memory it has an ATTESSA System with a higher sample rate (100 times per second rather than four), but does this really make such a huge difference?

Reason for asking is given in the attachment - wheelspin. The graph shows a data log from a nothingburger lap of Wanneroo. Particularly through Shell (left hander approx 216 secs into the log) the jagged blue line (rpm) indicates wheelspin - and lots of it. Not sure which end is causing the problem - my first move was to have a go at the suspension rather than the diffs. But the question stands - do R32 V-spec suffer from this nonsense?

post-5134-1129178868.jpg

what you need is an ATTESA controller, the 32s were very rear biased :D The controllers make a huge difference to how early you can get on the gas without too much oversteer or wheelspin

At the risk of firing this thread off on a tangent - does the R32 V-spec have an active diff?  I always assumed it had, but in the absense of hydraulic lines I now doubt it somewhat.

From memory it has an ATTESSA System with a higher sample rate (100 times per second rather than four), but does this really make such a huge difference?

Reason for asking is given in the attachment - wheelspin.  The graph shows a data log from a nothingburger lap of Wanneroo.  Particularly through Shell (left hander approx 216 secs into the log) the jagged blue line (rpm) indicates wheelspin - and lots of it.  Not sure which end is causing the problem - my first move was to have a go at the suspension rather than the diffs.  But the question stands - do R32 V-spec suffer from this nonsense?

Never seen an R32GTR V Spec with an active diff, only ever seen them on R33's.

What Duncan said is spot on, ATTESA controller required.

Plus it may pay to check the ATTESA clutch pack, as the power goes up they tend to slip and not deliver enough front torque.

:O cheers :)

Never seen an R32GTR V Spec with an active diff, only ever seen them on R33's.

What Duncan said is spot on, ATTESA controller required.

Plus it may pay to check the ATTESA clutch pack, as the power goes up they tend to slip and not deliver enough front torque.

:O cheers :)

The wheelspin feels much more like the inside rear spinning rather than a front/rear torque distribution - hence the fix is (broadly) more so to reduce the roll couple (Lower ride height), increase the roll stiffness (sorted) and to tighten up the rear diff. The wheel is sufficiently lightly loaded through Shell to not have much affect on the handling balance when it loses grip - it just annoys me because you cant let the thing drift out against the ripple stip on the exit of Shell during the run up to Kolb.

What you are saying about the ATTESSA pack is correct, however presently I have a surfeit of grip over engine output. Hence the car is still understeering - although this is halfway to being fixed also. Just time & money really, like everything.

Well you can certainly re-shim the rear diff as well if you are confident it is the inside wheel spinning. What system is the data logging from? Can you add wheel speed sensor input from both rear half shafts?

But until all 4 wheels are spinning under power out of corners you are not taking full advantage of the system :(

Well you can certainly re-shim the rear diff as well if you are confident it is the inside wheel spinning.  What system is the data logging from?  Can you add wheel speed sensor input from both rear half shafts?

But until all 4 wheels are spinning under power out of corners you are not taking full advantage of the system :(

Yeah, tightening up the diff sounds like the other best option.

I used the highly technical data logging method of getting a mate to stand on the inside of the corner to see what was happening. Unfortunately there are not any more inputs available for the data logger. (Although I would love to better get at most of what is available in the Skyline eg TPS, steering input, ATTESSA outputs etc etc.)

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