Having problems holding boost at high rpm. Its dropping from 18 down to 15. Its running a 3 port mac valve. With ams split dumps. I was thininking the recircs might be leaking or the boost controller is playing up. Surely the turbos can hold more than this. Ive heard of 28rs holding 20+ psi no worries.
These turbos will boost very high but their efficiency range goes down after 20 PSI. You either have a very big boost leak or the actuators do not have enough preload on them as said above, or they have a problem like a leaking diaphram. What boost controller are you using? Before the turbos were fitted they should have been synchronised and preloaded with an opening pressure of 12PSI.
Haltech is controlling in closed loop i think. I matched the actuators when i got them but they seem to be holding 10 psi.. Before i swapped the mac valve they used to hold 12 13psi. By themselves. I wonder if the new 3 port mav valve is screwing things.
Whatever came with the kit. Ended up getilting them to hold 20psi no problem. It was just a software setup problem.
