Stock Ultra 300 Avg. Speed 66-67 mph @ 7450 RPM
R&D Performer Kit Avg. Speed 72 mph @ 7800 RPM


Description of Parts
R&D Ultra 300 Ride Plate Kit
Part #: 121-30000
R&D Ultra 300 Aquavein Grate Kit
Part #: 111-30000
R&D Ultra 300 Pump Shoe Seal Kit
Part #: 161-30001
R&D Ultra 300 Anti-Cavitation Cone
Part #: 161-25010
R&D Ultra 300 Speed-up Module
Part #: 801-15300
R&D Ultra 300 Cool Air Filter Kit
Part #: 215-25000
R&D Ultra 300 Performance Exhaust Plate
Part # 331-35300
R&D Ultra 300 Deep Fuel Pickup
Part # 801-25100

Retail Price: $1081.67     

Additional Performance Upgrades

R&D Ultra 300 Sponson Kit
Part #: 121-25001

R&D Ultra 300 Waste Gate Block off
Part #: 611-26001
R&D Ultra 300 Powershot Fuel Controller
Part # 801-25000

 Parts/Kit Overview

The R&D Ultra 300 Performer Kit was developed to improve overall handling, reduce pump cavitation, and increase top speed performance with strictly bolt on performance parts without engine modifications! The entire Performer Kit installs quickly and very easily with basic instructions and hand tools. Each component part in the Performer Kit can be used as a stand alone product. The new Kawasaki Ultra 300 engine platform is significantly different over previous Kawasaki models with its new type supercharger. The new supercharged Kawasaki engine is a fantastic power plant; however the 950-1000 pound weigh-in without a fuel load has left the engineers at R&D a big challenge to work with. The R&D Performer Kit will add up to a 7 mph increase in top speed performance with superb handling benefits. The R&D Performer Kit will transform a great boat into “The Perfect Boat”. The R&D Performer Kit parts have been offshore endurance and closed course race tested and have chocked up some impressive offshore wins in the 2011 season.

  • The R&D Kawasaki Ultra 300X Ride Plate has been fashioned after our dominant and championship winning GP-1200R and Kawasaki 15-F ride plate designs with a few new tricks added. The Ultra 300X ride is re-angled over stock along with the addition of the new R&D stepper concept to add top speed improvements. R&D’s Ride Plate concepts are the only aftermarket designs to dominate in Offshore, National, and World Championships, and to be used and endorsed by Factory Yamaha and Kawasaki racing teams for nearly a decade! The new Ultra 300X ride plate from R&D is “The Perfect Ride plate” with a great balance of speed and handling with no compromises!

  • The R&D Kawasaki Ultra 300X Aquavein Intake Grate Kit has been designed and developed to deliver the ultimate handling and speed performance in recreational, offshore, and closed course race conditions. The R&D Ultra 300X Aquavein will deliver quicker acceleration, higher top speed performance and a much smoother and more predictable ride over the O.E.M. intake grate. Low speed and high-speed turns are a breeze with new found control. The R&D design offers a smoother “recreational friendly” off throttle deceleration allowing a more comfortable and smoother ride. The secret to the R&D Aquavein’s hook up performance is in its patented, award winning, and championship winning wing and twin bar, super deep channel design. The well proven R&D top loader Aquavein wing concept has been used exclusively by Factory Kawasaki and Yamaha racing teams to win every Pro 1200 and Open World Championship for a full decade! Bolt on an R&D Aquavein top loader intake grate and experience why R&D is the top selling intake system worldwide. Each new R&D Ultra 300X Grate will also include “FREE” a special “Speedo Unlimiter” spacer plate which will allow the ECU to adjust the throttle plate to a true full throttle position allowing the Ultra 300X to really perform. So, where else can you get a scoop grate kit that will allow a 4 mph speed gain on flat water????

  • The R&D Pump Shoe Seal kit for the Ultra 300 is now available. The three piece Seal Kit stuffs up the unwanted cavities in the pump shoe and the oem intake grate that aid in producing cavitation. This kit allows you to seal up the area between the intake grate and pump shoe, which will reduce cavitation and increase pump efficiency and performance.

  • The R&D Kawasaki Ultra 300 Anti-Cavitation Pump Cone Kit will reduce overall internal pump cavitation within the Kawasaki Ultra 300’s offset reduction/compression nozzle design. The O.E.M. Ultra reduction/compression nozzle is offset 5 degrees, while the O.E.M. pump cone/bearing cap remains straight which causes uneven pressures within the pump and reduction nozzle. The R&D Anti-Cavitation Pump Cone is offset 5 degrees and reshaped to match the O.E.M. reduction nozzle offset promoting even pressures, which will substantially reduce cavitation, increase pump hook up, boost acceleration, and increase top speed performance.

  • The R&D Ultra 300X Speed-up Module was developed to easily install and interface between the stock speedometer and the O.E.M. ECU to recondition and regulate the Htz rate which will allow the Kawasaki drive by wire throttle system to operate at a 1-1 ratio (No Boost Limit Control). The new R&D Speed Control module cancels out all top speed controlling throttle plate manipulation from the ECU. Without the R&D Module, the ECU can regulate the throttle plate which lowers air flow volumes, and boost levels into the intake manifold plenum restricting top speed. The R&D Speed Control Module allows full boost levels to be achieved which produce a 3-4 MPH speed gain on a box stock Ultra 300X. The R&D Module will allow all aftermarket bolt-on parts to perform to their full potential. The R&D Module interface is undetected (stealth) to the ECU, so no warnings, codes, or stored information to worry about. The R&D Module plugs into the O.E.M. wire harness super easy in 5-10 minutes. A 3-4 MPH plug and play speed gain in less than 10 minutes! No tools required to install.

  • The R&D high performance Cool Air Filter Kit will improve acceleration and top speed performance by increasing air flow and reducing air temperatures that enter directly into the Ultra 300’s air plenum box area. The O.E.M. air plenum box on the Ultra 300 is a great design that will flow plenty of air. However, the air that feeds the plenum box is heated by the engine. R&D has created an easy to install “flat filter” that installs directly in place of the large center access inspection cover located directly under the main glove box. The R&D Flat Air Filter insert will allow unrestricted fresh and cool air to enter the air plenum box area which will add power you can feel and a nice high performance tone. The R&D Performance Filter Kit also features two filters, one for each of the surge and blowoff protection valves. The O.E.M. surge valve recycles compressed hot air back into the air box plenum at idle and under deceleration conditions. The R&D surge and blowoff valve filter kit removes the air recycling hoses which will keep the hot air from entering the air plenum box reducing the engines intake air temperatures. The R&D Ultra 300 Air Filter Kit offers great performance tips on how to remove the restrictive air vent hoses which will further reduce the under seat ambient air temperatures. The R&D Filter system does not remove or alter the O.E.M. plenum box in any way, therefore there are no questions to be answered regarding water ingestion! The R&D Filter Kit is easy to install with no modifications required to the O.E.M. parts.

  • The R&D Ultra 250X Deep Fuel Pickup is designed to maximize fuel volume. The stock fuel pickup is located housed in the gas tank three inches above the bottom of the tank. This leaves approximately 5 gallons of lost fuel in the bottom of the tank. The R&D Deep Fuel Pickup relocates the stock fuel pickup to the bottom tank in a vertical position. The new positioning allows for 24 percent more riding time per tank of gas. An absolute must for long recreational rides or offshore racing.

  • The R&D Kawasaki Ultra 300X Pro Series Sponson Kit was designed and developed with all new generation performance concepts in mind to deliver a whole new level of handling and speed performance with offshore and closed course race proven adjustability options. The R&D Pro Series Sponson Kits have been extensively offshore, race track, and 1 and 2 up recreational tested to guarantee a comfortable setting for any riding style or condition! The R&D Ultra 250 Sponson Kit will deliver higher top speed performance and a much smoother and more predictable ride over O.E.M. sponsons. Low speed and high-speed turns are a breeze with new found control. The secret to R&D’s new generation concept is in the backing plate design with an aftermarket first, low pressure, low friction concept that breaks up and relieves speed robbing drag within the sponson’s backing plate channel. The new R&D design staggers the sponson blades fins water trapping area to pick up less water in the front and more in the back. The stagger/step-up concept greatly reduces chine walk in high speed corners, while allowing more rear end grip. There is also a higher end recreational/race setting with enough grip for the best of pro’s! Finally there is an aftermarket sponson kit that really does it all! More top speed due to less drag, less chine walking, racer preferred rear end grip, and unmatched straight line stability.

  • The R&D Waste Gate Block-Off kit is designed to block-off the inconsistent OEM waste gate. The cnc machined part allows the supercharger to deliver its boost without premature pressure loss from a leaking waste gate. Kit comes complete with gaskets and hardware.

  • The R&D Performance Exhaust Plate kit replaces the restrictive OEM exhaust honeycomb filter that Kawasaki recommends inspecting or replacing every 25 hours. The R&D exhaust Plate eliminates excessive exhaust heat and flow restriction produced by the OEM exhaust filter. Improved exhaust flow decreases back pressure and heat, and increases performance. The exhaust Plate also features smaller water ports that decrease water to the water box, which eliminates hard starting conditions from wet spark plugs.

  • The R&D Powershot fuel injection tuner will deliver increased horsepower, acceleration, and stronger mid-range performance by delivering a higher performing air to fuel ratio (A.F.R.) to the engine. Many of today’s high performance fuel injected four stroke muscle craft have a lean A.F.R. R&D Performance has tested, documented, and analyzed the O.E.M. fuel maps on every current fuel injected four stroke watercraft, and pre-programmed and coded the new R&D Powershot fuel injection control module to safely alter the O.E.M. fuel map to a higher performing and safer A.F.R. (richer). More horsepower, greater acceleration and stronger mid-range are the result when the proper A.F.R. is achieved and is tuned for optimum performance. The R&D Powershot is fully adjustable on the fly (with the engine running, observed and tuned while riding), and will accommodate a wide range of adjustability to properly performance tune the A.F.R. for any combination of aftermarket parts. The R&D Powershot will add horsepower, reliability, and adjustability to any electronic fuel injected two or four stroke watercraft engine.

NOTE: R&D Performance has tested, data logged, and documented that the 2011 Ultra 300 has an overall lean fuel map at wide open throttle. R&D suggests that the R&D Powershot Fuel Control Unit be installed and WOT range be richened to 12.0-12.5 AFF. R&D Part # 801-25000

NOTE: R&D Performance suggests that high quality 91-92 octane fuel be used exclusively in the Ultra 300. 


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