This is all a bit difficult as there are so many starting points. Firstly in the UK most people work in HP. kW's is pretty much unheard of. Easy to convert with a calculator.
The other factor is rolling road losses. Just in my head I tend to work on a factor of 1.2. So.... if the wheel HP is 100 then the engine HP is 120..... simples. But you hear all sorts of figures and clearly all rolling roads not only supposedly read differently - but also different wheel to engine factors are used. At least that is how I understand it. The only reasonably meaningful comparison is cars that have attended the same rolling road and what their power figures are. Locally there appears to be folklore as to whose rolling road reads high (flattering) and whose reads low (probably nearer reality). I always go to the same rolling road so that way I can make my own comparisons. There is also a decent Alfa tuner near by - they always take their cars to the same rolling road - so I can compare what I have done, sort of, with figures he gets for his (very developed) work.
Here is my situation. I had my 33 back from the rolling road last week - and it said 170HP engine and 142 torque. To work that back I took 170HP x 0.8 and then converted it to kW. It equalled roughly 101kW.
This is how my engine is configured. 1800cc, high compression pistons, Omex ecu, wasted spark, original 16v manifold (slightly modified) but large straight through system (no cat), BMW injectors, trumpets with large filters, race alternator, ported heads, lightened flywheel, fully balanced, 1.2 Sud gearbox, big wing sump, standard cams, 146 oil pump, baffle plate and so on. As you can see there are a few things in there and it probably is reasonably accurate at around 170HP. Clearly as you know the factory figure for a standard (non cat) 16v was 137HP. Having spent £1000's I have achieved what I feel is a realistic +33HP. It feels to me to be about 170HP compared to other cars that I am aware of.
Interestingly, I build almost exactly the same engine about 10 years ago, minus the ported heads. On the same rolling road I achieved 169HP. I don't think the porting I had done, was particularly scientific and am pretty certain there was no flow bench work. So, although these heads were expensive (impulse buy!) in my mind they have given me 1HP...... eek!
Going back to your car, if I work the maths - it comes to 134HP. From the web you can see that 33 16v cars with cats were 98–101 kW (133–137 PS; 131–135 bhp) at 6,500 rpm when new, supposedly. Clearly I have used some pretty arbitrary factors in coming up with a figure, but you have to use (guess) something. One way of looking at it is that with the work you have done - it is back in line with what the factory first produced. Does that make you feel good / bad / happy / sad?
Let me know your thoughts. :-)