Its also going to depend on the abilities of the driver you are (potentially) racing, or their own perceived abilities. My mate has a 911 and claims he races everywhere, on the few times I've been in the car with him, he drives rapid, but not as fast as I do, he also admitted he does not put his foot to the floor, whereas I do on a daily basis, heck, in both my cars I see the red line on a daily basis, its there for a reason.
Had a mate in NZ with a Toyota Altezza Gita (IS300 sportcross), drove it once, it was quick, but not 911 beating, wasn't as quick as my Skyline GTS-T, Nissan Cedric Cima and maybe only just as quick as my 2.5L Mitsi Diamante. Heck, my work jeep in NZ was a 1.6 Vitara, lifted and offroad tires, yet I used to go through the twisties faster than drivers of Holden Commodore V8s, simple reason? I was prepared to use 100% of my cars performance, but they only used, and probably only had the capabilities to use 30% of theirs.
I raced a Gallardo a few weeks, but I had no delusions that my car was in the same league as him, he was clearly playing with me, and I'm sure he enjoyed it too, even though he could have left me for dead, but then he probably likes his licence too.