Mario Kart

[HPdesk]

My brother have made 39 secs for the Peach Circuit in the time trial session. I don't know how, my fastest time is 51 secs. Is there any cheat that he could have used ??? he told me that his speed was full at oll time. I tried to find it ou on the internet, but i've only found this cheat for N64, and i don't think it works cause it says to presse C-Up and C-Down. What is it ??? Directional button ??? does it work for Game Boy Advanced ???