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So, when you guys do your EJ and awd into MY and L series, do you get awd boxes with diff ratio to suit rear diff ie 3.7:1 or 3.9:1 or do you have to get and stick in an EJ car type rear diff ratio, coz we all know they gotta be the same

just wondering !

Well I can't speak for the others but I feel its a lot easier to just get a diff the same as the gearbox. That is, gearbox takes priority.

Salvaging an original part on the project car at the expense of the finished product isn't something I normally do. That is, if I had a 3.9 final drive on say, a beige MY wagon and I had a 4.11 gearbox going into it, I'd change the rear diff to a 4.11 rather than go hunting for a 3.9 gearbox. Matter of fact I'm doing that soon.

OK , having read my post I ain't sure I asked the whole question

Given all my diff ratios are 3.7:1 , are any awd EJ boxes 3.7:1 or do I prepare myself to know to get 3.9 or 4.1 or something for the rear, should I eventually go EJ.

And given the difficulty I had keeping the Brumby up with a 2.0 EJ Impreza driven by a 'hat' today, I am wondering if EA82T is gonna be enough to satisfy me.
I agree Tim, I wouldn't really base a purchase upon rear diff ratio either but just need the info there in brain to chew over, while I get EA82T going !!

Most EJ boxes are 4.11, some are 3.9 or 4.44.

Absolutely no point in retaining a 3.7 driveline, and buckleys of finding one in an EJ powered car!

You will need to update the diff to one of a matching ratio to your EJ gearbox, be it 3.9, 4.11 or even 4.444

that's what we need to know and wasn't sure, thanks

so , the splines, they all the same or do we need axles too ?

Whats different is actually whether or not it has splines at all. All the R160's I've seen with splined side shafts have had 23 splines. There's also the type with the inner CV's integrated into the diff, and there's also a female stub style too.
And if you count the old Datto's there's the U-joint sides too!