If you're going circle track or road racing, there are a lot of anti-siphon modifications and custom fuel curves required for sharp response and drivability (the key to winning). 

In 2008 this series scored the coveted SCCA Triple Crown, the GT-1 Championship, the American Sedan Championship, Rookie of the Year award in the O'Reilly All Stars series and Runner up in the Series, Set the track record at Sebring International Raceway and won the CFR SCCA Championship, both Won and Runner Upped in the USBA Jet Sprint Boat Championship and the list goes on.... you get the idea...

These carburetors are serious stuff.  Not off the shelf part numbers to generally fit your combination.  They are custom built for you, are fully prepped and ready for action. You won't believe the throttle response and "driver feel" this series offers and best of all... you can bolt it on and go racing.

This Series of 4150 carburetors includes these features:

• HP main body
• Available in cfm ranges from 780-1040
• Adjustable air bleeds
• Billet base plate
• Adjustable throttle response (compensates for track conditions)
• Built in alternate calibrations
• Electronically wet-flow calibrated
• Road race or LH floats (your choice)
• Clear sight plugs
• Stainless plate screws
• Custom sized needle and seats (titanium on alcohol models)
• Stepped boosters
• True race fuel curve
• Live-engine tested
• Techline access
• Wet-flow dyno sheet for easy jet selection

Priced as low as: $590.00/2 circuit gasoline or $690.00/alcohol