I'm quite sure your 1.8 also comes with VVT on both cams just like the 2.0.
Main difference is the smaller displacement, lighter weight crankshaft with
four instead of eight counterweights (if I remember correctly), smaller dia
bearings, smaller turbo (IS12 instead of IS20/IS38, but you know that) etc..
Perhaps there's some more (valves, cams etc.). Remember there's also some
difference between GTI and R. Pistons both geometry (compression ratio)
and alloy (higher Ni, Cr and Cu contents on Clubsport, S3 and R versions),
exhaust cam (intake cam is same), perhaps exhaust valves and piston jets,
of course IS38 turbo instead of IS20. Add uprated clutches/DM flywheels
and shorter gearing on manual versions.
Same crankshaft and crankcase between all 2.0 except the low-power 180/
190/204 HP Miller cycle version (Tiguan, A4 etc.), which is more familar with
its 1.8 predecessor. I do have almost all the documentation, but it's some
years ago I've read it last time.
Any link to adding MPI to a EA888 3G? I'm highly interested as my DLBA is
the only Euro EA888 3G lacking MPI. Despite that my exhaust remains clean,
suprisingly clean, contrary to previous versions even though they had dual
injection/DI + MPI. Guess that's due to the increas in fuel pressure and it's a
good sign with some relation to IVD.
On a side note: The DLBA's pistons are made from the same alloy as the S3/R
ones while they share the CHHA/CHHB geometry. Pretty much same internals
as current Audi A4/A5/A6 and Porsche Macan 245 - 265 HP versions, probably
same as Mk8 GTI, but I didn't compare PNs yet. So far I just know the Mk8 has
a new (Garret?) turbo, HP pump (and probably injectors) and a steel oil pan.