OK, it looks like I was a bit high, but not out of the ballpark. Add a little blower boost, and we're into at least racing gas compression range, if not the low side of alcohol-burner territory. A supercharger forces more mixture into the cylinders than atmospheric pressure can, effectively raising the compression ratio. It looks like somebody at the dealer didn't do his homework, plus there was no recalibration of the electronics or chassis dyno testing done before releasing the car to the customer. Thanks!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!