This is a very nice sleeper GH Sigma fitted with a G63B Turbo engine!
Here is some more information on this neat Sigma:
'81 GH Sigma
Engine: MPI G63BT 2.0 Single Cam
Exhaust: 3" Stainless from Exhaust Housing to 3'' Magnaflow Muffler
Suspension: Monroe Shocks, Kings Springs, Nolethane Bushes
Wheels: 1981 Spec Polished Peter Wherrett Specials with Whitewalls
Modifications: Balanced & Shotpeened Rods, Forged Ross Racing Pistons 30thou OverAutronic SMC 1.4v Management with 1.9 chip, Twin Bosch Coils & Twin Ignitors, Turbosmart BOV FMIC with Polished Piping, VN Throttlebody, Custom Inlet Plenum, 560cc Evo 7 Injectors, Custom Highmount Steampipe Manifold (heatwrapped), Garrett gt30 BB Turbo 0.63 Rear Housing, Full 3" Stainless Exhaust with deleted Screamer Pipe, 50mm Trust External Gate, Oil Cooler, Braided Lines & Speedflow Fittings for All Fuel & Engine Oil Lines, Hydraulic Clutch Conversion, Button Clutch - Exedy 8 puck cushion button, JAP 5 Speed, Custom Tailshaft, Mitsubishi Scorpion Disc Brake Diff with 3.3 gears, Autometer Oil Pressure & Boost Guage, ARP Head stud kit, Valve Springs, Small Porting, Cometic Head Gasket, Plumbed the screamer pipe back in.
Stereo Audio / Visual: Clarion source Unit, JVC 6" Fronts
Dyno Proven Power: 221rwkw on 23psi (297.1rwhp) wheelspin on Dyno Pump fuel and a little octane booster. Hopefully crack the 300rwhp soon