I've seen quite a few people mentioning about cars improving speed/handling etc but nothing confirmed. In testing cars myself a few seem out from their official (Social club or In-Game, ignoring IGN for now) stats.
I drive Route 68 a lot due to good XP (if you leave timer to at least 4 mins before crossing the line) so can usually get within a few tenths of a second on repeat runs with any particular car. It obviously favours top speed over anything else with no need to slow down and my best solo time with no slipstreaming is just over 1:52 in an Adder with Entity a couple of secs behind and all other Supers or better Sports just behind that between 1:55-2:00 or so. Whilst playing around the last couple of days a few things stood out -
Testing unmodded Coupe's to decide which to buy, the Exemplar is the fastest - but the Ocelot F620 is only just behind by a fraction and well ahead of the equally statted (on paper) Felon GT. The Oracle is decidedly mid-pack despite being the fastest top speed and acceleration according to the stats. There were no handling issues on this track.
Driving my fully modded Comet I can actually get around the track a fraction faster than my fully modded Carbonizarre, faster than all the other sports and just a touch behind my Entity - even though on this high speed track (and speed being key evidenced by the Adder vs Entity result) it's on paper top speed stats lack a little.
There's nothing conclusive again as the other stats like acceleration will have an impact but having driven most cars multiple times it does feel as if some things have changed but could of course my driving ability may also have progressed with the game, I'd consider myself "competent" at racing with a near 150/150 W/L record. It could of course be the case that the Rockstar stats have always been out but until recently the acceleration/top speed ones have seemed largely in the ballpark in comparative driving for me at least.
Anyone know if anything has changed or not for sure?