Work on the Gulfstream GIV began in 1983. The Gulfstream GIV was introduced and made its first flight in 1985. It entered service in 1987. The biggest differences from the GIII are FAR 36 Stage 3 compliant Rolls Royce Tay 611-8 engine, a four foot longer cabin, and 340 nautical miles extra range.
The GIV SP version entered service in 1993 and has 1,400 pounds more take off weight, 7,500 pounds more landing weight, a redesigned fuselage that allows one inch more headroom, and some minor system changes.
3,880 nautical miles
2,041 cubic feet
169 cubic feet