• Stock 4JJ1 HP3 effective stroke: ~5.8mm
• Stroker effective stroke: ~10.5mm
• Net increase: +4.7mm
• Effective stroke increase: ~81%

Fuel delivery in an HP3 pump is directly related to plunger stroke. An ~81% increase in effective stroke translates to a massive increase in theoretical pump output, making this shaft suitable for high-power applications where the factory pump becomes a limitation.

• 🧰 CNC Machined Precision: High-accuracy stroker profile for consistent pump output
• ⚙️ Massive Fuel Volume Increase: ~81% effective stroke increase over stock
• 🔥 High Power Capability: Supports aggressive injector and turbo combinations
• 🛡️ Built for Load: Manufactured from high-strength materials for sustained rail pressure
• 💰 Cost-Effective Alternative: Big pump output without moving to an entirely different pump platform

• Holden Colorado RC – 4JJ1
• Isuzu D-MAX – 4JJ1
• Isuzu MU-X – 4JJ1 (up to 2016)
• Any 4JJ1 application running a Denso HP3 pump

• 1 × FuseTech +4.7mm HP3 Stroker Shaft (CNC-machined)

Installation instructions not included — professional fitting required.

• Professional installation strongly recommended — HP3 requires precise assembly
• ECU tuning required to safely control rail pressure and EGTs
• Rail blank recommended for sustained high rail pressure (available here)
• Suitable injectors and turbo system required for high-output builds
• Contact us to confirm stock availability if timing is critical

• 💸 Buy Now, Pay Later: Afterpay, Humm, Klarna & Zip available
• ✈️ Free Express Shipping Australia-Wide
• 📦 Diesel performance specialists — not general parts resellers

For off-road / competition use only. Fuel system modifications may affect compliance. Check local regulations before purchase.

Q: Do I need tuning after installing this stroker shaft?

A: Yes. Due to the large increase in pump output, ECU recalibration is mandatory to safely manage rail pressure, injection quantity, and EGTs.

Q: How much power can this support?

A: With suitable injectors, turbo system, intercooling and tuning, this shaft supports very high-output 4JJ1 builds. Actual power capability depends on the rest of the fuel and air system.

Q: Is this a drop-in upgrade?

A: It is designed for Denso HP3 pumps used on 4JJ1 engines. Due to the aggressive stroke increase, professional assembly and inspection are recommended.

Q: Is this a new component?

A: Yes. Each FuseTech stroker shaft is brand new, CNC-machined, and manufactured specifically for performance use.

Q: Why is a rail blank recommended?

A: The massive increase in pump output can sustain very high rail pressures. A rail blank eliminates the factory pressure relief valve, allowing you to run higher sustained rail pressure without bleeding off fuel.

Q: What's the difference between this and the 1KD HP3 stroker?

A: The 1KD HP3 stroker is 1.3mm, designed for 1KD-FTV engines. This 4JJ1 version is +4.7mm (~81% increase), specifically for 4JJ1 HP3 pumps. Much more aggressive stroke increase.