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I did a bit of pressure and flow testing on my CIS with the following results:

924 measurements:
20C control pressure 0.5bar
hot control pressure 3.4bar
system pressure 4.7bar
system pressure full load 4.4bar
fuel delivery full load 600g/minute (820mL/minute)
individual injector delivery at three different plate positions:
16/18/19/19g
37/39/40/40g
74/76/77/77g (max deflection)
system pressure 20 minutes after pump off: 2.5bar, no dribbling.

Most of this is OK according to spec but I was wondering if anyone can comment on:
Is the injector balance reasonable?
Is it worth adjusting anything apart from the cold control pressure?
Is a system pressure drop at max load normal or indicative of a weak pump?

[Fasteddie313]

Did you swap the injectors to other injector lines to see if the flow differences followed the injector or the line?

The % difference between them is much smaller at high load than low load so that is a good thing.
If they all have nice spray patterns and the differences are acceptable to you then I think you should put the leanest injectors toward the front of the engine in order from front to back..

Does it idle good enough for you?
I think NA injectors are pretty cheap to get anyway aren't they? If you want to change them..

I think this is for your car..

[safe]

I would't touch any of the pressures. System preassure is not worth messing with, warm control pressure is fine.
I would change the injectors if they are the reason for the differences in fuel. A nice spray pattern can also make big difference in how the car runs an idles, I don't think you will notice any power increase.
Would be a good idea to change around the injectors to see if the "low injectors" follows.

If your fuel pump cant deliver the specified amount it could be worn or the in tank fuel pump (if you have one, -80 and later) maybe isn't working.
Could also be weak wiring, oxidation at the cables and terminals, oxidations at the relay and fuses etc. Check voltage at the fuel pump with the car running, then check at the fuse, then at the battery to se how much voltage drop you have to the pump.

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