Ok first thing first Drift Champ is a PS2 game. Secondly I have heard of problems with Magic's booting Jap games on American ps2s and finally the V7 and the Magic series don't seem to get along well. I'd say send the game my way but I get Initial D Special Stage in 9 days or so. Now I have had fine sucess with Japanese PS1 games but Initial D will be the first test of the Japanese PS2 functionality. Note on my V4 board I did a rather "unorthodox install" and the V4 is incapable of the double media check that the V7 sufferes which could be what you are suffering from.
JAP 60GB PS3 (release date)
37000 L V7 Ocean Blue Matrix Infinity BB Navi (.32)
30001-R V4R Magic ICE 91f3+ PS2 Linux (2.4.1)
10000 V0 No Mod, PSP-1000 1.0 FW 100K release model
PS2 Linux Kit (BB Navigator Installed)
Scph-5501 Stealth, All Sega Systems
Cube with Save, Xbox 1.0 Modded