In this video I give my impressions of using a K04-064 turbo on the 1.8T engine as found in a MK1 Octavia VRS. Is it a good match for this engine and for a 300bhp power goal?
Summary
Power comes on at around 2750RPM.
Strong power to 5000RPM plus. I don’t think the turbo has any issues maintaining power to redline. It is supposed to be good for 300bhp and I don’t see any reason to doubt it.
Around town it can be a bit spiky but keep the revs below 2500RPM and it’s fine.
On country roads it not a big problem to keep the revs above 2750RPM.
On freeway/motorway/autostrada the gearing means the car is turning quite big revs for the speed. When the revs are high it becomes harder to modulate the throttle but this could be a mapping issue rather than a turbo problem. In an ideal world I think a diesel gearbox/gearing would suit the turbo better.