[AI question] Race position related performance boost

Dear Forum members

I've observed strange effect on my AI only races. Regardless of the performance file leading car is always faster than the rest, regardless to their performance value.
Let me explanin a bit more.

Lets say Car 1 has lower bhp and grip than Car 2. But suddenly Car 2 takes the lead at the first corner of the race , after this event Car 2 is never able to catch up.
It makes me feel that Car 2 received some strange performance boost or Car 1 got some performance degredation.
It is like some race position related performance adjustment.
You can also test if you set same bhp and grip for all CC cars in the performance file. Overlapping still will occur because lapt times of the second car will be 0.2-0.3 sec
slower than leading car and so on on....22nd car will be 0.2-03 sec slower than 21st.

So did somebody observed the same ? If so , can this effect to be adjusted via magic data for example ?