You still have the chance to use the edit option, use it wisely ...Assetto Corsa is pretty inaccurate, especially because they use table readout physics ...
150 bhp is pretty unrealistic, they would be more than 3 sec behind, per lap (race pace)
This article is pretty bad - its really bad journalism - there are personal opinions in the article (ie. F1 sounds better than GP2, which is an opinion and not a fact) ....
This article in fact was not even thinking about if AC can do such "realistic" calculations ... this here reads like advertisment by Kunos, a "so called" simulation
Correction: I did accidentally exchange Reiza with Kunos - oopps apology.... still i stand behind my opinion ... this article is bad journalism - and using a sim to determine how big the gap is is ridiculous - I would say the same for any actual top sim (ie. rF2) avaible right now
For those who still have some doubts, you can find the formula quite easily (the one including drag only) : top speed is reached when the drag vs power equilibrium is reached (no i won't post it, time to do it yourself, since you have "doubts").