They are good when they are new. For 20000-30000 km.
After that their spray pattern on low pulsewidths goes to shit and they start misfiring on idle.
I wish I took a video of the injector bench, but those injectors at low pulsewidth were not spraying, they were taking a piss.

BTDT a million times now.

Will receive car back from bodywork shop these days as it will be painted and will restart adjusting it. Will also swap to separate boost controller as I suspect the pierburg valve of the car is far from being precise. Will also move the 72mm sensor into the 85mm housing and try to adjust it, will keep you updated. Thank you so far for the good piece of advice posted here.

Boost is tuned, little 1.6bar spike then constant 1.5bar boost. It's not that I can't tune it, it's the fact that the turbo solenoid valve seems to not be so precise on higher boost values.

ME1.5.5 it's a hybrid ecu, narrowband, indeed operating principle may be close to Me7, but this does not mean that it has same behaviour and precision.

And yes, I don't know how to tune the new MAF, no one was born a genius, I mentioned my experience is limited on these ecus. All I said about it is that I tried the diameters square ratio method, which is described all over this forum, but no one except one user here suggested MAF offset correction also, which sounds pure logical now once it was explained.

I would give it to someone who has an idea if I lived in a civilised country and not at the end of the world. In my country there are 2 cars like this, one stock and the other is mine. Closest Opel tuning company is in Germany, 2000km away.

Parts take from 1 to 3 weeks to arrive, no matter what I order.

Having these great opportunities in this wonderful country that I live in, I am forced to find myself the hard way a solution to make this car work, no matter if it has MAF or not, if turbo goes via stock solenoid or via MBC, etc.

I thank you all for precious piece of advice, don't want to bother anymore with my actions on this car, considering both lumpy idle and MAF calibration subjects received a certain answer, topic can be closed. Will open a new one once the setup is ready, of course I will try to keep both MAF and N75 active, if that will be possible.

Regards,
Alex

The ECU does not see more than 2550mbar. But you don't need an MBC, it can just be tuned to a fixed WGDC value.
Nothing to do with "being precise" or not. The only thing a MBC is good for, is to put it in parallel with the N75, to make sure the boost does not spike over a certain value.
It is basically ME7. Yes it has pretty much same behaviour, and I don't see why you are talking about "precision". I don't think you quite understand what this word means in this context.
Fit the stock MAF, then tune the injectors to be perfect.
After you are done, fit the new MAF, and tune it again to be perfect.
Like this you can tune completely unknown injectors and completely unknown MAF, for which you have no specifications at all.
So what country is that?

Also, if you already know how to log the ECU and how to flash it, then I am sure you can be helped online for a fee.

My objective is not to diss your efforts, but you just did the 3 biggest no-no's that apply to tuning these cars:
1. Fitting a BOV.
2. Removing a MAF.
3. Fitting a MBC.
Add to that the fact that you make bold claims about "precision" when not fully understanding what you are doing, and you don't come over too well, that's the thing.

If asking for help you need to be more specific, for example:
I changed the MAF, then changed map X and map Y. The car was doing Z and I logged values P and Q to confirm.
Also, first thing will be to fit a recirculating valve if you want to get this sorted, as well as fitting back the stock MAF and linearizing the injectors correctly. After that actual tuning can start.

Here is one Astra G Coupe Z20LET with stock M1.5.5, stock head, stock intake manifold with stock throttle body, GT3076R turbo 0.63 exhaust A/R, 830cc DEKA injectors, MAFless tune, removed both lambda sensors, with fuel economy better than stock car, idle is smooth like stock but on 950rpm because of more good idle oil pressure with hot oil. ECU controled boost and as you can see full spool 1.45bar on 3700rpm and flat torque curve from 3900 to 5000rpm. For reference only, on that dyno fully stock Astra H OPC(240hp) is 150kw on wheels

I might go there in Spring.
If you don't have it dialed it in by then, I'll sort it

Whats wrong with Romania i dont know ?........In your country you have one of the world fastest street Nissan R35 GT-Rs (8.9sec 1/4mile), 8.8sec Nissan Pulsar, several 9sec cars and many 10sec cars, performance tuning in Romania is not bad at all.

Btw I am from Bulgaria, but as you see on dynograph, its not the problem to tune Z20LET engine here