All you will do is mess up your tranny. I have messed around with it. In my opioion 1st has the best pick up, Since Im swapping out the engine I really dont give a **** about my tranny right now. Already Re-Built it once, dont give for the engine/tranny anymore. So I usually hit 1st and skip 2nd and go to 3rd when Im havin fun. The Vtec Screams in 1st. Its fun stuff going down hills and ****. But In my opioion dont mess with it unless your ready to swap it. Ive heard that 0-50 you should stay in D3 and hit D4 around there. You will know when to shift from hearing and reading the engine..Latz