is this the same as the systemax?

The lower is essentially the same as the Holley Systemax II, but the upper's major difference is it has provisions in the plenum for an additional/auxiliary set of fuel injectors. The reason for this was that these were originally produced before larger than stock size injectors were common or available in the aftermarket, so in order to meet the demands of a hot rodded 5.0, you had the stock injectors in the lower intake and another set of stock injectors in the upper plenum to give you more fuel flow.

I heard the vortech lowers were somewhat restrictive and the systemax was the same intake with some port work from holley essentially, its a 5.0 truck lower.