Nice Hilborn injection for small block Chevy. Setup for gas. Throttle linkage is free and shafts are tight. Hoses are showing wear. At some point did have a threaded port drilled in one runner but has been plugged and filled will not affect function. Ser# 3339 purchase July 1965 by George's Speed Shop Dayton Ohio. Call or text Chuck 660-886-6384. Thanks