Hello, here is the problem:
I have 1.4bar chip installed and my coop boosts only up to 1bar and holds it all the time on all gears. No overboost at all. Needle just trebles at 1 bar and no more. My specs are:
lancia evo I turbo - recently rebuilt
evo 6 fmic - checked, no leaks
hks ssqv 3 bov - new
k&n filter - new
walbro 255 fuel pump
tipo 16v inlet camshaft
stock exhaust
stock ebv
compression is 12 12 12 10.5
fresh silicone pipes all the way

I` ve tried to fit my 1.3 bar squadra chip and nothing changed though it showed 1.3bars two years ago. the problem appeared after my car was repaired from some front collision and cylinder head was also rebuilt . maybe it is coincidence.
what else should I check or replace? I got no ideas (

Must be the wastegate - sounds like the boost controller isn't restricting the boost to the actuator, so it's opening at its base level (presume you have a 1-bar actuator)

Well, I have a stock wastegate but it was recently refurbished when the turbo was rebuilt.. So i suppose that it should be fine. As for EBV how can I check it? Can the fuelling or injectors be the reason?

Unlikely - the fact that boost is holding near-perfect at 1 bar suggests that it's being controlled at that level

You should try a manual bleed valve in place of the EBV - that will confirm or eliminate the EBV

Ok, thanks, I`ll try it

Well, I`ve fitted PRV and there is some progress! It shows 1.2 bar when the valve is closed. That really seems to be the wastegate.. Can you advise what model will fit my turbo and be able to hold 1.4 bar?

There will probably be an adjuster on the actuator - usually a threaded bar. I cant remember which way you screw it but that may help

get a midi vac on the actuator vac hose and see what pressure it can hold.

then you can adjust it to what it should be.

to hold 1.4bar you will need some thing like a 0.8 bar actuator.

What turbo have you got fitted?

Thanks for suggestions, but what is midi vac? I have a stock turbo rebuilt to lancia evoI specs.. actuator seems to be stock either