The Hyundai Sigma engine is a series of V6 piston engines from Hyundai Motor Company, based on the Mitsubishi 6G7 engine. The Sigma engine family began life with the simple V6 name. Displacement ranges from 2497 to 3497 cc.

2.5L (G6AV)

The DOHC G6AV (also called the 2.5 D) is the small 2497 cc version. Bore is 83.5 mm and stroke is shared with the 2972 cc at 76 mm. Output is 162 - 173 PS at 6,000 rpm and 20.8 - 22.4 kgm at 4,500 rpm.

Applications

3.0L (G6AT/G6CT)

The DOHC G6AT and G6CT (also called the 3.0 D) both displace 2972 cc. They share the 2.5's 76 mm stroke but use a larger 91.1 mm bore. Output for the older G6AT is 185 - 205 PS at 6,000 rpm and 24.6 - 27.1 kgm at 4,000–4,500 rpm, while the G6CT produces 187 - 196 PS at 5,500–6,000 rpm and 26.5 - 27.2 kgm at 3,500–4,000 rpm. The older SOHC G6AT 3.0 S produces just 141 - 164 PS at 5,000 rpm and 22.9 - 24.5 kgm at 2,500–3,000 rpm.

Applications

3.0L LPG (L6AT)

The L6AT displace 2972 cc. They share the 2.5's 76 mm stroke but use a larger 91.1 mm bore. Output is 135 PS at 4,500 rpm and 23 - 24 kgm at 2,500 rpm.

Applications

3.5L (G6AU/G6CU)

The G6AU and G6CU (both also called the **3.5 D **) are the large 3497 cc versions of the Sigma engine. Bore and stroke are both larger at 93x85.8 mm, respectively. Output is 203 - 225 PS at 5,500 rpm and 29.6 - 31.8 kgm at 4,000 rpm for the older G6AU and 195 - 220 PS at 5,500–6,000 rpm and 30 - 32 kgm at 3,500 rpm for the newer G6CU. The 3.5 D has a cast iron engine block and aluminum DOHC cylinder heads. It uses Multi-port fuel injection, has 4 valves per cylinder, and features forged steel connecting rods. It is designed to run on "regular" unleaded gasoline rather than the premium fuel used in many other high-output V6 engines. The US-market version produces 197 PS at 5,500 rpm with 30.3 kgm of torque at 3,500 rpm. It was introduced with the Kia Sedona minivan in 2001.

Applications