I don't have the specs but I can assure you, that the difference is minimal and not noticeable with the newer systems. 75fm is still faster, but like I said, it's not noticeable, especially in certain classes of racing. You probably already know this, but all things being equal except fm or 2.4, you're reflexes will adapt to whatever you're using and as far as lap times are concerned, the overall difference will most likely be in the hundredths of a second if you're a top tier driver. I will get the specs from airtronics sometime this week and post it