Depends on what you want your car, the 4-2-1 header gives HP gains through out the whole RPM range and the 4-1 header gives greater HP gains in the high RPM range. So you decide what you need.
Good Luck with the fly ride.
"I love my life a quarter mile at a time"
Good Luck with the fly ride.
"I love my life a quarter mile at a time"
