Talk:World Tour/BMW M2 Special Edition/@comment-27403942-20180213035425/@comment-31458611-20180213130058

"Not a good ratio." Be your tuning a bit of an overkill or not, rest assured the ratio actually got slightly better. According to your own data,

Before: 0401-5050 392.7 km/h @1214; speed/rank efficiency = 0.323 After: 0501-5050 417.5 km/h @1278; speed/rank efficiency = 0.327

This is due to this car's particular rank distribution percentages. For the same reason, what did a little harm was the level 1 nitro, which gave less than 1.5 km/h for a 16 increase in rank fat.