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  • 3 Barrel Holley carb and conversion kit

3 Barrel Holley carb and conversion kit

SKU:
$25.00
25 615 $25.00 - $615.00
Unavailable
per item

Complete modified 600 carb, it is now a 450 CFM 3bbl.

Or: Instructions and a special plug to convert your Holley Vacuum Secondary Carb to a 3 BBL for improved fuel mileage and response. To be used with a OPEN plenum intake design. Like is used on Chevy inline 6 intakes.

A 600 CFM converts to 450CFM Good for 250

A 750CFM converts to 562CFM Good for Hot 250 and 292

If a complete carb is ordered, a new Aluminum Holley 600 or 750 is used and converted, a adjustable vacuum can and spring kit are also added to carb.

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 In this case 255 inline Chevy 6 cylinder. The modded carb is equal to 450 CFM and performs flawlessly. When in normal cruise RPM's, the carb runs one 1 primary throttle blade and when power is needed, both secondaries will then open providing the CFM's for power. As shown, this carb delivered almost 21 MPG going on highways ranging from 55-75 mph.

I know you are asking yourself, why convert it to a 3 bbl when the 600 4 bbl should also perform well. When running both primary's at cruise speed, the throttle position is not very far open and you are running on the idle circuits on a small engine. This is a inefficient fuel / air mixing circuit. When running a single primary, the blade will be opened further, promoting better fuel/ air mixing with the venturi .


Cam is a same as my Thrifty cam at www.12bolt.com . I sell a instruction sheet and the special plug to modify either a 600 or 750 Holley. They take different plugs.
The secondary opening rate is adjustable on these carbs to tailor it to your engine.
 

  • Home
  • Store
    • Valve Covers
    • Side Covers
    • Performance Cylinder heads and Parts
    • Exhaust
    • Accessories
    • Alternator and Power Steering
    • NOS GM Inline 6 and V8 Parts
    • Turbo Related
    • Bolt In Lump Kits
    • Breather Adaptors
    • Pistons
    • Rods
    • Intakes
    • Mounts
    • Timing Covers
    • Engines
    • Camshafts
    • Shortblocks
    • Engine Stands
    • Harmonic Balancers
    • Bearings-Gaskets-Oil Pump
    • Torque Plate
    • Distributor Blueprinting
    • Carburetors
    • Air Cleaners Used
    • Vehicles
    • 12 Bolts and Parts
  • Inline 6 Articles
    • Me and My Turbo
    • Sissell Literature circa 1988
    • Sunset Chevy
    • 2 HP Per Cubic Inch
    • Cotton Perry
    • Six Abuse
    • Six In a Row Makes it GO
    • Soup of the Day
    • Stovebolts Storm Again
    • Stovebolt Storm Part 2
    • Straight Six Shooter
    • The Buzzin Half Dozen
    • Turbo Tornado
  • Lump Head information
    • General Head Information
    • Inline cylinder head flow
    • Bolt in lump installation instructions
  • Services
  • Gearing Calculator
  • Photos
    • 12 Bolt Pics
    • Inline 6 Pics
    • 292 Turbo EFI
    • Shop Tour
  • Videos
    • 12 Bolt
    • Inline 6
    • Customer Cars
  • Links
  • Tech Tips
  • Wanted
  • About Us
  • Contact
  • Inline Engine Build Ideas
  • Jacob's Journey