I'm needing a important information about XU10J4RS valve springs. Will now use solid lifters and change valve springs

I will put some useful informations about valve springs and retainers, and need other

External valve spring
ext diameter - 27.4mm
int diameter - 19.9mm
decompressed height - 48.6mm

Internal valve spring
ext diameter - 18.5mm
int diameter - 13.45mm
decompressed height - 38.6mm


retainer - valve seats
for internal valve - 13.3 to 19.3
for external valve - 19.3 to 28.2



Found solid lifters with 32mm of diameter, OEM parts from a car... if somebody wants more info, MP-me



Informations I need:

- What's the installed spring height for this engine?
- Who knows the information of load/height for the OEM springs?
- Can I trust in using the OEM retainers for high load springs, such as 300lbs springs?
- what brands make special valve springs for this head?

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Citroen ZX 16v

XU10J4RS turbo