Power loss after head replacement (ZD30)

[Jardan341]

Hey everyone, recently had the cylinder head replaced by a mechanic on my zd30 and when I got the car back I immediately noticed it has lost about 20% power loss in every gear. Top speed is now 120kph and it used to be around 150kph. Struggles massively up hills and is near impossible to overtake.
I have replaced the following:
All vacuum lines
MAP sensor
Fuel filter
Neutral position switch
these made absolutely no difference

the car makes 14psi boost
starts straight up and idles fine everytime
EGR blanked and swirl mod done
no engine codes

Feels like its starving itself of fuel but not sure, could the mechanic have messed up the timing by a fraction? Never had power issues with the car but as soon as I got the car back it was lacking power and has not gotten better or worse since. Any suggestions would be appreciated

 

[tweak'e]

check the basics first. fuel filter, air being sucked into fuel. put a clear bit of hose on the injection pump return line. any bubbles check hoses for cracks and vacuum test the fuel spill line. real easy to miss the vacuum test and have a loose spill line connection. thats critical as it lets fuel into the engine oil and bye bye engine.

one of the common problems will all head replacements is people putting the largest sized head gasket on. zd30 only has two sizes afaik.
otherwise check valve clearances are correct, check timing chain all lines up, check cam timing is right. last one is a pain but check the cam gear pin. they are known to get bent/break and throw timing out.

 

[Jardan341]

I had taken the car back to the mechanic that did the work and he suggested there might be an issue with the turbo itself but that doesn't make sense to me as it still makes 14psi of boost, just makes a loud whistle noise when cold but that's been like that since I've had the car, haven't checked timing yet so I guess I'll have my mechanic take a look at that and see if he maybe made a mistake or if something is wrong with the fuel system.

 

[tweak'e]

won't be turbo.
could be air restriction. saw one where someone dropped a glow plug seal down the intake.
check the main butterfly is opening fully. check its open at idle then unplug the electrical connectors on the solenoids and test drive. could be some one got vac hoses mixed up and butterfly is staying half shut.