I think its the relative ease with which "fast" can be achieved compared to a bygone era.
These days - a tune only F6 or 335 car will go deep into the 11's flat 12's
If I had to get those numbers in my old XE ESP - it would be heavy duty engine , trans and diff mods , and then would most likely be a pig to drive on a regular basis with fouling plugs , no aircon and a fuel bill that would rival our national credit card debt.
So keeping things in perspective - a "fast" car
these days would definitely be something that can transcend a tune only car and is running into the high 10's - low 11's as it would require more than just a "tune" to get it there. Injectors , fuel pump , pulley size change , exhaust , intercooler upgrades , tyres etc etc.
I guess where I'm coming from is that it needs to be quicker than a stocker with just a tune as there are so many of them getting around lately. XR6T , F6 , GS315 SC and GT335 SC. Plenty of 12 sec cars on our streets and at the strip.
so - IMHO - if your ride is in one of the brackets below - it probably goes something like this......
14 bracket - glance your eye in the rear view mirror for that golf GTi about to overtake
13 bracket - glance your eye in the rear view mirror for that M series 135I beemer nipping at your heels
12 bracket - glance your eye in the rear view mirror for that stocker G6ET with the granpa driving - he's in a hurry and he's just overtaken a GTS...
11 bracket - glance your eye in the rear view mirror and check out the front of that ferrai - F40 - beautiful - wish he'd catch up so I can check out the rest of the car....
10 bracket - gee - that Koenigsegg has a bit of grunt - side by side - can probably stop faster than i can though......whoooooooaaaaaaaa
9 bracket - Hmmm - I reckon If my reaction time was abit quicker - Mr Bugatti Veyron would be in trouble , meh - I can fit more junk in my Falcon trunk anyways. LMAO........
All just a bit of fun - but seriously folks - any street car in street trim capable of consistent
low 11's and under is a weapon in my book.....