Also the Viper has fully adjustable KW coilovers....so with a team of race engineers that Dodge has been known to send with the car....I would imagine it would be faster than a ZR1 around a track like Buttonwillow.
The ZR1 is like a hyper hyper GT...it's like a 599 GTB -10 on the interior - 350 lbs and plus 26 hp.
The ACR is very similar to there race only Challenge coupe Viper they were selling a while back, quite frankly I am amazed they were bold enough to sale a car like that in the showroom!
It's hard to beat the black with red stripe ACR for sinister looks though!