Mike I have not done any comparison to a Sixpack but the factory four barrel intake is quite good as I can remember the disapointment after laying my hard earned $4.00 an hour down for a LD340, and getting little to no performance increase. The 340-360 A body cars do well in stock eleminator and the intake and carburator are one of the reasons in my opinion.
Getting old just means you were smarter than some and luckier than others.
