Thank @mitu , I've tried another ROM for CTR and now it's working fine, but I've tried six differents for V-Rally 2, none of them working. So I think @LineOf7s is right about it, sadly. The only good news is that I'm not the only one who want to play that game with more than one friend, if I'll make it work one day you'll be the first to know it ;)
I've got another question, and it seems a waste of time open another topic because it still multitap related. ISS pro evolution 2 allow to play up to four play, and the multitap work without problem, but the input the game ask for come from port 1-A, 2, 1-B, 1-C and none of my 4 joystick control the player 2, while it result plugged in. I think that if I could plug in a fifth joystick should work (just assuming) but there's a way to config the fourth joystick to control player 2 instead of player 1-D?