I just bought a Transgo Shift Kit from Summit Racing, i dont want to do the manual valve body change, i wanna be able to just stick in Drive and Go. Im reading the box and it says it holds 1st 2nd and 3rd gear to any Rpm, i just dont understand this, please help me understand. Why do i want to hold it to any rpm?? Explain in idiot terms, cause im a newbie here