My S1 RST has run 3 engines over the years from what I can tell regarding its history.

It ran a 1.9 Long block CVH which ran 240 and 270BHP depending on where the boost was set.

The bottom end was then swapped for a 1.8 Zetec unit. At a recent rolling road it made 225BHP at 18PSi where people felt he was a little conservative with the figures so probably accurate! From what I can tell the spec is the following:

Stage 3 head?
Piper 285T camshaft?
Piper Vernier pulley
Calibra Turbo or Omega pistons?
Bosch KE Jetronic
MFII 5th Injector.
CR Turbos Hybrid T3 - 2WD Cosworth compressor housing with .55A/R wheel, ball bearings with -31 actuator (TSF02 for anyone wishing to know the code).
Pace chargecooler with larger charge radiator
Single box exhaust system
MkV Gearbox with pedal assembly and Helix 4 paddle clutch.


The ?s represent where I am a little unsure of the spec. The graph however was not too bad with the fuelling being more than safe. If I knew more about the internals I may have been tempted to turn the boost up a notch but for now it seems to be running well at 18PSi:



With the exception the clutch (a Helix 4 paddle ; don't get one if you can avoid doing so!) it is actually a very drivable engine.
Whilst I know a Zetec would slay it for power and potentially reliability there is something about the sound of a turbocharged C(Z)VH.

I guess if I was to go further with mine I would probably look to getting the pistons and rods changes as well as changing the fuelling system to a standalone system.