Civic Si vs Lexus IS300

I got aem CAI and dc sports cat back, and some stereo shit and i'm a big guy, bout 6'4" 300lbs. Welp me and my friend lined it up, he was completely stock, except of course of the fast and the furious green neons lol. So we are stopped in the middle of the rd and we do the 3 beep thing and take off, kinda shitty start cause he didn't know to go on 3 beeps so i stopped and (only got a few feet) then we he gets next to me he goes so i went, had him all the way to middle of 3rd about 60-70 when i let off (40mph zone), and he continued on his way lol. My clutch is even slippin and i took him ;D So don't be intimidated by those is300's. Oh yea his car smelled like rotten eggs i think his cat was clogged or burned up lol Welp thats my story and i'm stickin to it