"I used to go about a half a season and the bottom of my intake plenum would have dirt or basically just a mud consistency on the bottom and down the runners.  I was using K/N type oiled filters that need to be washed and re-oiled with dirt still getting through filter which created blow-by and rebuilds more frequently. My motor builder kept asking me if was cleaning my filter out enough. I then talked to you and tried your filter and it worked just like you said. I did not need any grease around the seal area of filter. I have used your filter for a full season and washed it multiple times throughout the season it has held up great.  I looked at my motors intake plenum at the end of this season with your filter and it was completely clean!  Your product works exceptional, it works just like you guys at R2C said it would! 

Ray Bollinger

Asphalt Modified CFD 4150 Bases and Filters

Asphalt Modified CFD 4150 Bases 4 hole
Asphalt Modified CFD 4150 Bases 4 hole

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  • SSR10600B  14" x 3"
  • SSR10643B  14" x 3 1/2"
  • SSR10644B  14" x 3 3/4"
  • SSR10601B  14" x 4"
  • SSR10602B  14" x 5"
  • SSR10604B  14" x 6"
  • SSR10605B  14" x 4 3/4"
  • SSR10621B  14" x 5"
  • SSR10635B  11" x 6"
  • SSR10642B  11" x 4"

Asphalt Racers..............Bolt on immediate Dyno-proven double digit gains!


R2C's computer designed CFD 4150 Air Cleaner Bases and new Black Hex Series race filters provide double digit gains in horsepower and torque for Asphalt racing engines.


*New Black Hex Race Series Filters

  • Maximum Dyno Proven Horsepower and Torque Gains
  • Improved Booster Signal for Better Throttle Response
  • Faster Lap Times
  • Simple Maintenance and Long Life

      The Most Powerful Base/filter Combination in the World!

Months of design evaluation and flow bench testing, followed by extensive dyno and track tests (now over 1100 independent pulls!) conducted by the most respected names in race engine and carburetor assembly, have resulted in the best flowing, highest power producing air cleaner bases for Holley 4 barrel race applications. Every application from Stock Cars to unlimited Late Models and Big Block Modifieds have achieved significant gains in power and response/driveability.

R2C engineers developed each precision base shape to augment the venturi profile of the popular 4150 series Holley carburetor, resulting in dramatically smoother entry profiles and reduced restriction and a much stronger and consistent venturi/booster signal, allowing precision racing carburetors to perform at optimum levels and engines to produce increased power and torque. When used in conjuction with R2C Aspahlt Modified air filter configurations, nothing comes close to the performance advantage R2C CFD 4150 4 barrel bases offer pavement Modified racers.

CFD 4150 4 barrel air cleaner bases are offered in three configurations, allowing racers to select the precision contour that maximizes overall performance based on their individual applications.

* Patents Pending





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