What I do with GT2. Is get all Golds on the B-liscense.
Then i finish all the others, barely passing in some cases.
(I still hate the slalom)
Then I use the S2000 with a modded tranny, and maybe a chip.
Then I do the enduro at Trial mtn (295 HP limit).
The Spoon S2K can win easily against the grocery getters in this one, and only pit one time.
You win 150,000 and the Denso Sard Supra. You can keep it to win other series or sell it and have 400.000 for your nefarious pursuits. Personally, It is good for the Unlimited HP series, and the 680 HP enduro at GVS.
If you do it right you should only have 8-10 days elapsed (GT2 time).
If you happen to be a collector, Start watching the Used car lots for the Subaru 22B.
These three cars are a good base for winning all the rest of the races over 246HP.
This is my "Get Rich Quick" Scheme for GT2.