User blog comment:MignightHawk/Just a little list of GTAO misconceptions/@comment-25295528-20150805094816

Just to let you know, comparing to other cars ain't the best way to gain an understanding of how fast a car is, I'll also tell you that the handling.dat files don't correspond to the in-game appearance of speed (the Mammatus does about 10 mph according to Handling.dat, same with Hydra). We take supplied game data, I've given up on racing Adders and Cheetahs side by side, it just isn't reliable enough, and quite frankly, even though the First Person Speedomters' speeds are masssively different from what you'd expect them to be, they're turning out to be more reliable than other sources. I've seen the "Adder vs Z-Type" video, where it became so popular, but controversal. I've given up on comparing the cars against each other. I've been a mechanic for nearly 2 years now, and racing two cars side by side isn't the best way to test a car's potential, if only there was a dyno (dynamic monitor) in-game to test the vehicles to their maximum potential.