MSV Racing OptiFlo™ "Phi" High-Volume Impeller Kit for CR500 Outlaw Kart Engines

Up to 25°F Cooler. Up to 2.12 HP Recovered. More Consistent Power Every Lap.

Ask any top CR500 Outlaw Kart engine builder and they'll tell you the same thing:

The cooler your engine runs, the more power it makes.

As engine temperature climbs, horsepower begins to fall. Once a CR500 reaches heat-soak territory, performance drops dramatically and valuable horsepower is lost when you need it most.

The MSV Racing OptiFlo™ "Phi" High-Volume Impeller was engineered specifically to help CR500 Outlaw Kart racers maintain lower engine temperatures, reduce heat soak, and maximize horsepower throughout an entire race.

Proven Benefits

✔ Up to 25°F Lower Operating Temperatures

✔ Average 1.5 GPM Increase in Coolant Flow

✔ Up to 2.12 Horsepower Recovered

✔ Reduced Heat Soak

✔ More Consistent Power Throughout the Race

✔ CNC Machined from Premium Alcoa 7075-T6 Aluminum

✔ Includes Water Pump Cover Gasket Set

The Problem: Heat Kills Horsepower

Most CR500 Outlaw Kart engines operate around 190°F under race conditions.

As temperatures continue to rise toward 220°F and beyond, the engine begins to enter the danger zone where heat soak starts robbing horsepower and performance becomes inconsistent.

When the kart in front of you starts fading late in the race, that's often heat taking its toll.

The goal is simple:

Keep engine temperatures down and power stays up.

Only One Cooling Upgrade Directly Increases Coolant Flow

There are only three ways to improve CR500 cooling:

• Larger radiator surface area
• Cooler air flowing through the radiator
• Increased coolant flow

For most Outlaw Kart racers, radiator size and ambient air temperature are fixed variables.

That leaves coolant flow.

This is where the OptiFlo™ "Phi" Impeller delivers a measurable advantage.

Engineered to Outperform the Competition

Rigorous flow bench testing and real-world Outlaw Kart race testing demonstrated significant improvements over:

• OEM Honda Impellers
• Frank's MX
• Mino
• Apico
• AS3

The OptiFlo™ "Phi" Impeller utilizes computer-designed vane geometry based on Golden Ratio principles optimized specifically for the CR500 water pump housing.

Combined with extremely tight operating clearances, the result is dramatically improved pumping efficiency.

Performance Comparison

Competitive Impellers = Lower Coolant Flow

MSV OptiFlo™ "Phi" Impeller = +1.5 GPM Average Flow Increase

Temperature Comparison

Competitive Impellers = Higher Operating Temperatures

MSV OptiFlo™ "Phi" Impeller = Up to 25°F Cooler

Dyno Proven

Testing showed:

Up to 2.12 Horsepower Recovered Across a 1,750 RPM Range

That's horsepower your engine is already making but losing to excess heat.

Built for Competitive Outlaw Kart Racing

Whether you're running:

• Stock CR500
• Mild Engine Build
• 2mm Stroker
• 3mm Stroker
• 4mm Stroker
• Liger Hybrid
• Maximum-Effort Race Engine

The OptiFlo™ Impeller helps maintain lower temperatures and more consistent horsepower throughout the race.

What's Included

• MSV Racing OptiFlo™ "Phi" High-Volume Impeller
• Water Pump Cover Gasket Set (2 Gaskets)

Everything needed for installation.

Remember:

Horsepower creates heat.

The more efficiently your cooling system removes that heat, the more horsepower your engine can maintain.

If you're serious about maximizing CR500 Outlaw Kart performance, reducing heat soak, and keeping power consistent from the green flag to the checkered flag, the MSV Racing OptiFlo™ "Phi" Impeller is a must-have upgrade.