If you are too stupid to read, will explain...
I dont use the cheat online, done few tests with it offline tho, its great to see how fast cars can go with (teorical perfect) slipstream.
PS: here goes some pics i saved, was lazzy to split the ones with the cheat on, but they are easily spotted, are the ones with crazy speeds and single player.
There seems to be 2 versions of the cheat, or even 2 completly diferent cheats, one from neo that does 680 and one from another guy (one i have) that enables 100% slipstream.
BTW, ask devs if you want, I already sent them all the info i could possible get, screenshots, replays, the cheat itself, how it works, what it does, the HEX and address that it pokes...
If you are too stupid to realize I am helping solving this, then kill yourself.
BTW, your original pic isnt real, even with the best cheat you cant get that fast... if its real then neo might just discovered gold in some chickens egg... the fastest i get was 406... and the wheels crash with the downforce and flip with the lateral force (check right wheel on the maxSpeed.jpg, its starting to crash)