the steel armed hubs from a 924s/944 fit bug axles -they have bug splines
-i just tried a bug axle in both a 1985 and a 87 turbo hub -alloy arms
-and they dont fit
alloy hubs are fine splined -steel armed are fluted splines, -the same as bug
the steel arm 944's use the exact same arm as a bug -the hubs are the same -drilled differently 'for arguments sake'
-they then as described above, have a 22mm factory spacer fitted
-they say the track -with this spacer is the same as an early 944 alloy 1985 arm and disc /hub
-so realistically, an alloy arm is 22mm wider than a steel arm
-the leter 87 onwards 944 have a wider hub - widerdisc -extra 25mm per side
-so if as matt says, you simply remove the stock spacer of the 944 steel arms -the track is the same -use bay window studs
-ps a brembo will catch a fuch -you NEED 7mm spacer -at least