If you have the need to peel your face back with speed, Dodge has the answer: the 2010 Viper SRT-10 ACR-X spec racer. It's a track-only, high-output version of the already brutal Viper SRT-10 ACR, and it's set to go on sale this summer.
So just how powerful is the ACR-X? It adds 40 horsepower to the stock engine's 600, thanks to 5-into-1 exhaust headers, the absence of catalytic converters and some other tweaks and improvements. It's not street legal, but at this level of ferocity, it doesn't need to be. For the full details on the car, check out our preview here.
But to see what 640 horsepower of V-10 fury looks like at 100 percent on an engine dyno, its right bank of headers glowing red hot, check out the video below.