The HW-24 was calibrated for Formula Vee in cooperation with AHS Motorsports. The AHS One Shot system required for Formula Vee. For that application, the HW-24 requires or benefits from some extra components which are available from us or AHS Motorsports (+44 1455 553052).


  • Butterfly Opening
  • Avenger Class Venturi/Body Design
  • Avenger Class Inlet Needle and Seat Design
  • Avenger Class Idle/Acceleration Nozzle Design
  • Works with Tillotson PrecisionJet and AHS AutoJet

For Formula Vee racing and other applications that may require mid-race restarting where the carburetor is out of reach of the pilot, the carburetor must be used with the One Shot system, currently available from AHS Motorsports and available soon from us. The One-shot system retails for £300 plus vat per kit.  One kit can run up to 2 carbs, and for £75 they offer an add on kit to expand that to 4 carbs.

For in-race control, add the Tillotson PrecisionJet or AHS Autojet controller (one controller per carburettor).

You will also need a manifold that will adapt your engine to the bolt pattern on the HW-24.  The inlet length of the manifold is also critical on certain engines. To purchase manifolds, contact Alan Harding at AHS Motorsports.

Primary Application

Formula Vee

Can be used in other two-stroke and four-stroke applications (four stroke applications may require addition of pulse hole).

Carburetor Settings

Formula Vee Engines vary by manufacturer, manufacture date, and tuning. Below is the factory setting for the HW-24A, but you will likely need to make some adjustment. Adjust the High needle first, then the Low needle; each in 1 minute increments. You should not need to adjust more than 10 minutes in normal conditions, but extreme conditions like hot or rainy weather may require additional adjustment.

Factory Setting:  L=0 turns 30 minutes (0′ 30″); H=2 turns 0 minutes (2′ 0″)

Fuel pressure: Initially set at 3psi and adjust if necessary

Weight1 kg
Venturi Diameter


Throttle Bore Diameter


Throttle Bore Range

Product Line


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