This is a Holley 0-80443 Marine Carburetor designed for large cubic inch marine engines where a mechanical secondary 4150 model 4BBL is required and has been modified for use with draw-thru supercharger applications.
Modified by Blower Drive Services (BDS) for use with draw-thru superchargers
Boost referenced power valve for proper enrichment under acceleration
Features a port in the main body for indexing the power valve to boost for draw through supercharging; Weiand B&M 174/177/250, Blower Shop, etc. blowers
Milled choke tower for balanced air flow
Novel U-Style vent tube, directs fuel/fumes back into the carburetor for safe operation while on rough waters
Power valve anti-backfire check valve kit provides power valve blow-out protection
Specialized calibration for marine supercharged applications, all fuel circuits balanced & calibrated
Gold Dichromate finish for corrosion resistance and classic Holley looks
Added shiny chrome finish bowl kit for good looks
Mechanical choke
30cc primary and 50cc secondary accelerator pumps for additional fuel under initial acceleration
Dual feed fuel inlets for constant high volume fuel delivery
Mechanical Secondaries for perfect off the line launches
100% wet-flow tested by Holley technicians to assure it arrives ready to run
All Holley Marine Carburetors are designed to meet Coast Guard specifications. A marine carburetors fuel metering system is calibrated to compensate for unique engine loads found on boats.
Specifications:
Barrels:4
Booster:Down Leg
Carburetor Use:Marine
CFM:850
Choke:Manual
Material:Aluminum
Finish:Gold Dichromate
Model:4150
Secondaries: Mechanical
Throttle Bore: 1.750 inch
Main Jets
Primary: 84
Secondary: 88
Power Valves
Primary: 4.5
Secondary: 4.5
Idle Bleed
Primary: .070
Secondary: .059
High Speed Bleed
Primary: .028
Secondary: .026
Pump Nozzle Sizes
Primary:31
Secondary: 31
Carb Installation Instructions:
1. Set float levels (idling) to bottom of sight plug. No more than 6-7 lbs of boost pressure (8 lbs HO racing engines).
2. Set idle mixture screws (engine warm) to max RPM or vacuum.
Recommendations:
Total Ignition Timing: 28-30 degrees
Minimum octane fuel: 91
** This is an open-box item, that is new and has never been used **