Rated “R” Series Carburetors

If you’re looking for a 4150/4500 carburetor that jumps right up on a tight converter and launches hard for nitrous fed engines look no further than our Billet Rated “R” Series. This carburetor come as a fully billet design (can be hard anodized black for $200.00 more) and has the fastest shift recovery on the market today. With over a decade of experience with multiple combinations, it’s a simple choice to go with. This carburetor is race track tested and proven with the  latest technology. Fill out our quote form and let IRD Racing Carburetors get you the tenths of a second you deserve.


  • Made with a full billet design
  • All materials are made in the USA
  • IRD Rated “R” Billet metering blocks fully tunable 2 or 3 circuit designs
  • Billet fuel bowls that hold 20% more fuel with big sight windows
  • Nitrophyl floats /drag or circle track
  • Jet extensions
  • Improved main body air entry for more flow
  • External linkage
  • Custom boosters per application
  • Adjustable air bleeds
  • Available for Gas, E85, Alcohol, Nitromix
  • Available in 4150 and 4500 styles
  • Track tested winning design
  • Customer Kendell Goin – Multiple cash days winner uses our Rated “R” carb