After school I raced my friends 96 auto basic mustang with 150 Hp. We were both travling at 40mph and had a rolling start I was beating him up until we reached 70mph, then he passed me up. Im thinkin I was doing sumthing wrong. While we were at 40mph I had it in 4th and when we took off I downshifted to 3rd and I was in 3rd for the rest of the race and we got up and over 70mph, my rpm meter was goin up so slow, I was waiting till it got between 6-7 to shift so I could use all of 3rd gear, is it good to use all of the gear or should I have shifted into 4th earlier?