MK3 7M diff ratio quesiton

[vas85]

Hi Guys,

I've got a spare torsen diff from a TwinTurboR halfcut I bought a while ago which I ended up selling (albeit keeping the tailshaft + diff).

I believe it's a 4.11 diff ratio, and the standard 7M is a 3.7.

If this is true, is it worth installing for a performance gain?

Also, how much do these go for these days, if say I was to sell the 1J Torsen Diff?

Cheers,
Vas

[dnegative]

They are the same money as the regular LSD diff's, they are a better diff but they fail quite reliably with added power

[Daddio]

Your JZA70R diff is a 4.1:1 (not 4.11) if it was from a manual, or 3.9:1 if from an auto. Torsen was standard on the R
The 7MGTE A70 auto diff ratio is 3.73:1 (manual is 4.1:1), and LSD was optional, not standard.
Both will hold stock power comfortably, TorSen will fail first as power increases, clutch pack LSD can be beefed up easily, TorSen cant. TorSen will be 'smoother' in carpark turns than a tight LSD.
The 4.1 will give a bit better off the line performance compared to the 3.73, but the 3.73 is better for cruising and for over stock power (assuming R154 ratios)
Good 4.1 or 3.9 TorSen, maybe $400 for the complete pumpkin, around the same for non shagged 3.73 clutch LSD (Perth prices, no idea on east coast as everything A70 seems dearer?)...

[vas85]

Thanks Daddio and dnegative. Very help info on the reliability aspects regarding the Torsen. My 7M is pushing about 200rwkw and has been for the last 11 years that I've had it.

Reading your post, are you implying that my 7M GT Limited A70 Manual has a 4.1:1?

In that case, there wouldn't be any benefit to going over to a Torsen other than the carpark turns (although my existing stock diff doesn't seem to be a problem).

[Daddio]

Probably...check the diff code on the build plate to confirm (assuming it hasn't been changed at some point)...I assumed my JZA70 would have the 4.1:1 Torsen, but turned out it had a 4.1:1 4 pinion open diff from factory (now a 3.9:1 Cusco 1.5 way)...there are often surprises