new Viper, 725hp on the roller dyno!

Video: Hennessey Performance Tests 2013 SRT Viper

[ame=http://www.youtube.com/watch?v=XWjAKyAPhi8&list=UU8Jgn2dTAEvsV9YezsV3mSQ&feature=player_embedded]2013 Hennessey Viper with Long-Tube Headers and 3 in. Exhaust Upgrade - YouTube[/ame]

2013 Hennessey Viper with Long-Tube Headers and 3 in. Exhaust Upgrade - YouTube

 

The dyno sheet in the video doesn't show anything close to 725, it shows peak power of 554hp at the wheels (same as stock) and a nice gain across the range, peaking at 25rwhp at 5000 revs. Maybe this vid is before headwork?

That said, the headwork is probably putting another 25-30 to the wheels. at 580 to the wheels it's still far below 725 at the crank, unless you're using 25% for driveline loss which is unreasonable in these cars. 15% is the standard. Point is, unless you're running a built motor with a hot cam, full exhaust, ECU, 725 crank is unlikely on a stock motor with heads and exhaust. No way does the Gen V have 80hp tied up like that.

The Gen II cars saw upwards of 40rwhp from headers/exhaust. The factory has clearly done a nice job on the stock Gen V setup.