JNasty4G63
Not trying to spark anything, but you're a little off. The GT3 that we were all comparing the Z06 to has no turbos. Its a natually aspirated 3.6L flat-six motor making 375hp. So, I would understand your questioning that if the Porsche was turbo. But, its not. Maybe you were thinking about the GT2, not the GT3. The GT2 is the pumped up, 480hp, lightened, RWD version of the standard 911 Turbo. Maybe thats what you were thinking of. Again, not trying to get anything started. Just wanted to clear that up.
Hilg
Yup, I was. Live4speed and I were chatting this very issue up pretty hotly just last week, and when I went to check the specs on the GT3 today (instead of the GT2), neither of them were on the Porsche USA website anymore (they were there as late as last week).
I've stated it several times, but everyone keeps saying that no one that buys a $70k car cars about gas mileage. The problem is, I think they really DO, and that's why Chevy worked so hard to keep the vette and Z06 from having a Gas guzzler tax. HP figures well above the 500 mark leaked out continually before the Z06's release, but came down to offer better fuel economy. Besides paying the tax extra over the already high sticker price, I don't think people want to be reminded every time they fill up that their car cost more, and STILL costs more to operate. The base vette is the first 400 hp car to avoid the guzzler tax in the US, and the Z06 is the first 500hp car to avoid it. Given that the Enzo and CGT have HIGHWAY mileage in the 12-13 mpg range (half that of the Z06, and even worse than a Hummer H1), I'd say that GM left quite a bit on the table on purpose. Tuners are talking of about 600 hp with just a cam swap. GM is talking forced induction for the Blue Devil so they can keep up the trend, and avoid the GG Tax for the 600 hp car as well.
Simply put, displacement is an easy substitue for A) Cost, 2) Technology and complication, and D) Overall engine size. Everyone on this thread seems to be chatting about this stuff in a vacuum. The vette's motor is actually SMALLER than most DOHC V-6s. MUCH less expensive, complicated, and Much more durable (ie capable of abuse). It is capable of an 8000 rpm redline, but Chevy restricts it to 7k (probably to avoid a servicing schedule more like other high-strung sports cars).
In fact, given the livability/abuse expectations Corvette customers demand, the Z06's perfomance is even more amazing. It kinda makes you wonder why some of the other cars it has been compared to cost so much more and are so high maintenance.