Got a 4x4 cosworth that i bought and rebuilt the engine (as it had blown up and was in bits in the boot!!!) Its had new pistons, bearings, full head overhaul etc etc. When driving it has no boost, nothing. No pull or anything. I have tried adjusting the turbo actuator and that has made no difference. Its running standard and a sierra 4x4 (2.9) wipes the floor with it. Is it something serious or a piping problem? Its had all new engine sensors, turbo overhaul, new boost pipes amal valve. I just dont know what it can be. The engine is running as sweet as a nut but there is just no power. I would be very very grateful for any help pointing me inthe right direction.