Solution for the lazy people:
1. get a peel p50 and have 69k credits ready
(The peel p50 is a summer barnfind car. You will obtain it while getting the barnfind achievement anyways.)
2. download my drag peel tuning setups. the car will take off like a space rocket now.
3. drive to the drag strip at the festival area and start a race there
4. laugh your asses off as soon as you witness the pandemonium
this insane car will run the strip in under 9.5 :D
PS: some people mentioned minor issues so here is help
1. ofc (if possible) fast travel to the dragstrip on the festival. this car cant drive in a straight line
2. if you cant find my tune, just do it by yourself. buy the best parts available.