maXpeedingrods T3/T4 Turbo Kit for Honda Civic, CRX and Del Sol D-Series

Important Fitment Notice

This is an aftermarket turbo-conversion kit—not a replacement for an original Honda turbocharger. These Civic, CRX and Del Sol models were naturally aspirated from the factory.

Installation requires mechanical modifications, oil-pan work, exhaust fabrication and ECU tuning. Although the package supplies several major components, additional parts will be required for a complete and reliable conversion.

Turbocharger Specifications

The supplied “wet drift bearing” description is awkwardly translated. The design is better described as an oil-lubricated floating or journal-bearing center section.

Understanding the 400-Horsepower Claim

The advertised 400-horsepower rating represents potential airflow under suitable operating conditions. It does not mean a stock D-series engine can safely produce 400 horsepower.

Actual output depends on:

• Engine condition
• Compression ratio
• Internal engine components
• Boost pressure
• Fuel type
• Injector capacity
• Fuel-pump flow
• Intercooler efficiency
• Exhaust restriction
• ECU calibration
• Ignition timing

Turbo manufacturers generally calculate maximum power capability from compressor airflow. That rating represents potential engine output, not guaranteed wheel horsepower or a safe stock-engine limit.

For a street-driven stock-internal D-series, the tuner should establish a conservative power and torque target based on engine condition. The connecting rods do not care what the turbo box promised.

T3/T4 Turbocharger Design

The T3/T4 configuration combines a relatively large compressor with a T3-style turbine inlet. The 0.50 A/R compressor housing and 0.63 A/R turbine housing are intended to balance airflow capability with street-oriented response.

Potential advantages include:

• Stronger midrange and top-end airflow
• Support for future engine upgrades
• Common T3 mounting pattern
• Readily available wastegate and downpipe components
• Suitability for custom D-series builds

Spool response will vary with displacement, compression, camshaft timing, manifold design, exhaust restriction and boost target.

Front-Mount Intercooler

The included intercooler helps reduce the temperature of compressed air before it enters the engine.

Lower intake-air temperatures can provide:

• Increased air density
• Better knock resistance
• More consistent power
• Reduced heat soak
• Improved tuning stability

Charge pipes must be routed carefully around the radiator support, bumper reinforcement, air-conditioning hardware and body structure. Cutting or modification may be required depending on the chassis.

Oil Feed and Return System

The package includes oil-feed and return hardware, but installation still requires an appropriate oil source and a properly positioned oil-pan return fitting.

The return line must:

• Flow downhill from the turbo
• Avoid sharp bends
• Remain above the engine’s oil level
• Use heat-resistant hose
• Remain clear of the exhaust manifold and downpipe

A restricted or poorly positioned return can force oil past the turbo seals and create smoke that is often incorrectly blamed on a defective turbo.

Additional Parts Required

A complete installation may also require:

• Engine-specific turbo manifold
• External wastegate
• Wastegate dump tube
• Five-bolt downpipe flange
• Fabricated downpipe
• Blow-off valve
• Intercooler piping and couplers
• Air filter and intake pipe
• Larger fuel injectors
• Higher-capacity fuel pump
• Adjustable boost control
• Wideband oxygen sensor
• ECU or programmable engine management
• Properly sized MAP sensor
• Upgraded clutch
• Heat shielding
• Exhaust-system modifications
• Fresh gaskets and mounting hardware

“Kit” does not mean every fastener required by every chassis is included. Honda builders have been learning that lesson since dial-up internet.

Check Engine Health Before Adding Boost

Before installation, perform:

• Compression testing
• Cylinder leak-down testing
• Oil-pressure testing
• Cooling-system pressure testing
• Fuel-pressure testing
• Ignition-system inspection
• Timing-belt inspection
• Crankcase-ventilation inspection

Use Pro Street’s engine-health checklist for turbo builds before installing the kit.

A tired D-series may run acceptably while naturally aspirated and immediately expose ring, head-gasket or bearing problems once boost is added.

Fuel and Engine Management Requirements

Do not operate the engine under boost using the original naturally aspirated calibration.

Proper tuning must account for:

• Larger fuel injectors
• Fuel-pump capacity
• Boost pressure
• Air/fuel ratio
• Ignition timing
• Intake-air temperature
• MAP sensor range
• Rev limit
• Boost cut
• Fuel octane

A wideband oxygen sensor and datalogging are essential. An adjustable fuel-pressure regulator by itself is not a tune, regardless of how shiny it is.

Installation and First Startup

Professional installation and tuning are strongly recommended.

Before starting the engine:

1. Verify the turbocharger rotates freely.
2. Clean all intercooler pipes and oil lines.
3. Install the oil return above the pan’s oil level.
4. Prime the turbo with clean engine oil.
5. Crank the engine without starting until oil pressure develops.
6. Pressure-test the intercooler system.
7. Verify wastegate and boost-controller plumbing.
8. Confirm adequate fuel pressure.
9. Begin tuning at wastegate spring pressure.
10. Monitor air/fuel ratio, oil pressure and boost.
11. Check for oil, exhaust and intake leaks.
12. Reinspect the installation after the first heat cycle.

Materials and Temperature Ratings

The turbine housing is constructed from ductile iron and advertised to resist temperatures up to approximately 1,292°F. The alloy turbine wheel is rated for higher operating temperatures, reportedly up to approximately 1,652°F.

These are material ratings, not recommended continuous exhaust-gas temperatures. Excessive exhaust heat can still damage the turbocharger, valves, manifold and catalytic converter.

Emissions and Street-Legal Notice

This kit alters the vehicle’s factory induction, fuel and exhaust systems. No California Air Resources Board Executive Order number is provided.

Verify local emissions regulations before installation. In California and other regulated areas, the kit may be limited to competition or off-road vehicles unless specifically approved for the exact application.