This question must be the most common one I am asked but the answer is a complex mix of power, cornering ability, driver feedback and more. So here is an answer that I hope will capture some of that in a graphical form.
This is the lap times of the fastest 10 cars in each race at Brands Hatch on the same day. The range of the 10 best lap times is shown as a bar for each catagory of racing and the Arrow’s fastest lap time is the green horizontal line. The Arrow is not the quickest car in Sport specials but those in front are probably 70hp up on the arrows 150hp.