There is a good chance...15% loss is usually used on RWD or FWD cars. Of course we know the GTR is AWD. It has the semi-auto transmission and 2 diffs. to put power through..
560hp seems a little on the high side to me but considering the above, its not that far fetched.
I like both cars but with the GTR having a base price of around $80,000, and the ZR1 having a base price of around $104,000 the GTR seems a little closer to something we could afford(although I can afford neither). Of course these prices have been inflated and there still is a waiting list to own a GTR (hence the price). So while you may laugh because GTR's are selling for way over MSRP, please show me where a ZR1 is selling for its MSRP.
.....................Zr1...........GTR
Weight............3324........3814
HP..................638..........480
Torque............600..........430
City Mpg..........14............16
Hwy Mpg..........20............21
For being so different, they are actually pretty similar performance wise. The ZR1 being 500 pounds lighter, having ~160 more hp and 170 more torque, and almost $30,000 more expensive than the GTR...I sure as hell hope it performs better than the GTR, albeit not by much.
Id drive either, but the GTR seems a little more practical for everyday living. It actually has a rear seat which is good for a lot of reasons. Id like to see a normal 6-speed version with a clutch pedal. Perhaps then people wouldn't have to worry about breaking transmissions and could actually bring it to the 1/4 mile. Tho please keep in mind the GTR wasn't built to run down a straight 1/4 stretch.
If I had $100,000 to get a car..I would get neither of these. Id go with a new BMW M5. Four doors, full backseat, every luxury amenity you can think of and a 500hp v10 sounds nice to me.
Also im not sure how long the ZR1 will be out since GM is about to kick the bucket unless the government gives them a handout for all their hard work