"By using an aluminum block over the standard cast iron of the V8, the fuel-injected 90-degree Falconer V12 weighs roughly 500 pounds, some 100 more than Chevy's L98 V8. In return for the added mass, it also produces 686 horsepower and 600 pound-feet of torque."
I'm slightly relieved that they never released this beast. It most certainly would have been the end of Viper.
Edit: I really don't think they would have stuck a V12 in Viper to compete. They would have just stayed with the V10 platform, and all the guys would have moved to the Corvette V12 from Viper. Because that's the type of dudes that own vipers. The type of dudes that say, "Yeah that's cool, but it ain't no V10." That type of dude never wants to hear, "Yeah your V10 Viper is cool, right up until a V12 Vette rolls up."
Cool, I'd forgotten about that car. Falconer V12's had a bit of a following with the offshore boat guys for a while, good motors by all accounts, but were too expensive to make a dent in the aftermarket auto industry. A few hot rodders ran them and they'd definitely have had the cool factor. A few well coined guys have run custom ones - and there's a good gallery on Ryans site, some interesting examples Welcome to Ryan Falconer Racing Engines! - Galleries
The Audi/Lambo V10 is a fantastic engine. One of my best buddy's has run his 560-4 Lambo (same basic engine) in over 20 closed road events (sometimes 2000km each between closed and touring stages) plus numerous track days. Most of the cars' 46000km have been doing events, getting there, and normal servicing in between. Car never misses a beat, goes hard and he drives it like it was built to be driven. My old AMG C63 507 coupe required headers and a good tune with sticky NT01 tires to hang with it. Car is amazing, and clears a lot of road irregularities and bumps that catch out the Shelby's and Camaro's etc - forget a ZO6, they'd leave their spoiler behind on some of our roads at speed.
It runs good track times too.... though funny enough for 1-2 hot laps his tuned Urus is actually faster... but the heavy beast can't keep it up without the rotors on full red glow where 'as the 560-4 will just eat the laps up. The Urus is ridiculous, sub 3 seconds to 60mph after the factory offered him a significant tweak pre-purchase (off the records as it would not meet emissions), coolest SUV I have ever been around, amazing.