tuned derv ZS update

[ZS Phil]

Trial and error is the only way of really knowing but, as it sounds like you are doing, an educated guess as much as poss.
Looking through the catalogues of DSLA 145p injectors with a 2 stage spring doesn't leave that much choice to work through once orifice number and size are taken into consideration. I've done 200 tdis to death with several maps, I did try 300 tdi with custom brackets as per my build thread but that was with only a max fuel map as I hadn't learnt how to map at that point. I remember they were awesome low down but just drowned the engine with fuel once above 1500 rpm or so. Could be worth 're-visiting and playing with mapping to tone them down higher up the revs. Only problem is I'd have to buy more as I sold the nozzles on afterwards.
Obviously you are going to try the 6 hole ones and I'm doing my best to get some modified standard nozzles so I'm sure between us we can work out what works. Having tried 4 sets of injectors, 4 turbos, several wastegate configurations and 4 boost control methods along with countless maps I can empathise that these things cost money!
I'll keep you posted with the custom nozzles if I can get anywhere with it.