Viper engine

The Viper V10 is based on the Chrysler LA engine family and appeared with the Dodge Viper in 1992. It was conceived and prototyped as a Magnum 5.9 with two extra cylinders and a longer stroke of 3.88 in (98.6 mm).

The first-generation Viper V10 engine had a displacement of 7,990 cc (8.0 L; 487.6 cu in) and produced 400 hp (406 PS; 298 kW) at 4600 rpm and 465 lb⋅ft (630 N⋅m) of torque at 3600 rpm.[2]

The second-generation engine, also displacing 8.0 L, produced 450 hp (456 PS; 336 kW) @ 5200 rpm and 490 lb⋅ft (664 N⋅m) of torque @ 3700 rpm.[3] 1999 was the last year for forged pistons until the 5th gen engine was released in 2012. There was an emissions transition happening around this time that may have influenced this.

The third-generation engine, introduced on the 2003 Viper, had a displacement of 8,285 cc (8.3 L; 505.6 cu in) with a bore x stroke of 102.4 mm × 100.6 mm (4.03 in × 3.96 in), rated at 510 hp (517 PS; 380 kW) @ 5600 rpm and 535 lb⋅ft (725 N⋅m) @ 4200 rpm of torque after SAE certification in 2006.[4]

For the 2008 Dodge Viper, the engine's output was increased to 600 bhp (608 PS; 447 kW) @ 6100 rpm and 560 lb⋅ft (759 N⋅m) @ 5000 rpm of torque via a slight displacement increase to 8,382 cc (8.4 L; 511.5 cu in) and the use of variable valve timing, among the first utilized in a pushrod engine. The bore was now 4.055 in (103.0 mm), the same as Chrysler's 6.1 L Hemi engine.[5]

The 2013 SRT Viper kept roughly the same displacement but further boosted power to 640 hp (649 PS; 477 kW) @ 6150 rpm and 600 lb⋅ft (813 N⋅m) @ 4950 rpm of torque.[6] Since 2015, power was raised up to 645 hp (654 PS; 481 kW) at 6200 rpm.[7]