well u defenetly need the amp if u want ur subs to hit if u dont want them to bump well u can just hook them up to the door connections but they are going to sound the same as if u didnt had a system at all. Aight if u dont want to remove ur head unit u can buy a RCA CONVERTER they sell them at...
yup i say if your car is in good conditions you can do it without any problems, i have a 93 civic dx and it has a blown headgasket and it has 133 thousand miles on it and i drove it like that to nebraska and came bak then i went to texas and came bak with no problem at all i really though it...