HI-RAM 105MM Fabricated Side Mount Plenum Top for EFI Hi-Ram Manifolds Holley now has fabricated aluminum plenum to options for those of us with limited room in the front of our engine bays. The 4 mm thick aluminum side mount plenum tops resemble the older Ford EFI manifolds and will allow you to mount the throttle body on the side. This will allow for easier fabrication for boosted applications or for just a different look on your Hi-Ram manifold. Fabricated aluminum construction designed to mount on our existing Hi-Ram manifold bases. Available in silver or black finish. Models for both LS and 86-95 Ford 5.0 Style throttle body patterns in 95mm and 105 mm sizes.