The Holley 4150 Street HP carburetor uses the best features from Holley's race Bred 4150 HP carbs, but tamed for street and light competition use. The contoured main body from the 4150 HP carb has a tumble polished shiny finish. The Holley 4150 Street HP Carburetor metering system includes a timed spark port for a vacuum advance distributor and is calibrated for a hot street/strip engine setup for outstanding throttle response and drivability. A street HP base plate is used so there are plenty of vacuum ports for power brakes, PCV, etc. Best Value in a Dual Purpose Street and Light Competition Carburetor; Model 4150 Street HP; Mechanical Secondary; Double Pump / Double Pumper; Contoured Main Body; No Choke;