Edelbrock part #70855 Victor EFI Tunnel Ram base is a modern updated design to our very successful Victor Ram 2-R Tunnel Ram, which was first released over 35 years ago. It's designed for use with 468-582 c.i.d. standard-deck Chevrolet V8 engines with conventional rectangular port cylinder heads. This new and improved design has 7" long runners with close to 5.5 square-inches at the plenum, making it 25% larger than our current Victor Ram 2-R Tunnel Ram base! This is the ideal intake manifold for any modern high horsepower demanding application. Will fit Edelbrock Victor series race cylinder heads #77409, #77459 and #77609.