if you got to 50% of the game, you should've gotten a Jaguar XJ-R9 Race Car, it's the cheapest-best way to pass the league, it takes lots of effort to do it tho, right settings tires, etc...
now if you can't pass it that way, then pass the "Mission Hall" 's races: 30-34
and you will get the NISSAN R89C Race Car '89, you should not struggle with this car, and if still you can't do it,
then pass the "endurance hall" El Captain 200 Miles and you will get the TOYOYTA 88C-V Race Car (MINOLTA) '89. it should be a pieceo of cake with this car.
if you wanna buy a fast car on your own, then pass the Rally d' Capri in "Special Condition Hall (easy)", you can pass it even with a 200hp car and it takes less than 5 mins. you will get a car worth 265,000. just pass it over and over till you can buy a really fast car
