Product Description
JBtuned 2006-2011 Civic Si FA5 / FG2 Complete Fuel System
The JBtuned 8th Gen Civic Si Complete Fuel System is designed specifically for U.S.-market 2006-2011 Honda Civic Si models.
This system replaces the factory fuel hard line from the fuel tank to the engine bay with a complete PTFE braided AN fuel system and adds a dedicated 6AN return line from the fuel pressure regulator back to the tank.
Choose either a 6AN or 8AN feed line depending on your fuel-system requirements.
This system was developed on an 8th Gen Civic Si, including development on a turbocharged 8th Gen, so fuel-line routing and heat management were considered as part of the design.
Vehicle Compatibility
This fuel system is designed for:
- 2006-2011 Honda Civic Si Sedan - FA5
- 2006-2011 Honda Civic Si Coupe - FG2
- U.S.-market / USDM Civic Si applications
This kit is not designed for FD2 Civic Type R or other non-U.S.-market 8th Gen Civic chassis.
If you have a vehicle or configuration outside of the applications listed above, contact JBtuned before ordering.
Fuel Compatibility
This system is built using PTFE braided fuel hose.
PTFE provides broad fuel compatibility for fuels including:
- Pump gasoline
- E85
- E100
- C16
- M1
- M5
- Q16
- Other fuels compatible with PTFE fuel hose
PTFE fuel hose can also be used with regular pump gasoline.
Fuel Line Configuration
Feed Line:
Choose either 6AN or 8AN.
Return Line:
Always 6AN.
Fuel Line Material:
PTFE braided fuel hose.
The system replaces the factory fuel-feed hard line and adds a complete AN return system from the fuel pressure regulator back to the fuel tank.
The standard configuration is designed around mounting the fuel pressure regulator on the USDM driver's side of the fuel rail.
Choose Your Fuel-Rail Feed Location
One of the unique options with this system is the ability to choose how the feed line enters your aftermarket fuel rail.
Each option changes the appearance and routing of the system, so choose the configuration that best matches your build.
Side Feed - Tucked Under Intake Manifold
This option feeds the USDM passenger side of the fuel rail and routes the fuel line underneath the intake manifold for a cleaner, tucked appearance.
Side Feed - Rear of Engine
This option also feeds the USDM passenger side of the fuel rail but routes the line around the rear of the engine.
This routing places the fuel line closer to areas that may experience significant heat on turbocharged applications.
We do not recommend this routing for boosted applications unless the line can be properly protected from extreme exhaust and turbocharger heat.
Center Feed
The center-feed option routes the fuel supply to the center-feed location of the fuel rail for customers who prefer that appearance and configuration.
High-Horsepower Applications
For builds focused on maximum fuel flow and horsepower, we recommend using one of the side-feed configurations.
Designed With Turbo 8th Gens in Mind
We developed this system using a turbocharged 8th Gen Civic Si and route the fuel lines low and away from major heat sources wherever possible.
Every turbo installation is different. Turbocharger placement, exhaust manifold design, wastegate position, downpipe routing, and other fabrication can significantly change the amount of heat near the fuel system.
If your fuel lines will pass close to the turbocharger, exhaust manifold, wastegate, or downpipe, we strongly recommend selecting the High Heat Sleeve option.
Extreme exhaust heat can damage the outer braid and other fuel-line components regardless of manufacturer, so proper routing and heat protection are important.
Important Requirements
This system requires:
- Aftermarket fuel rail
- External adjustable fuel pressure regulator
- Compatible fuel pump
- Proper fuel-pump sending-unit configuration
- Appropriate engine management and tuning for your setup
This system is not designed to work with the factory fuel rail and factory-style fuel pressure regulator configuration.
The system includes the appropriate fuel-rail and regulator connection fittings based on the options you select when ordering.
OEM EVAP System Removal
The OEM EVAP-system area is used to provide mounting space for components such as the optional fuel filter and/or flex-fuel sensor.
The OEM EVAP system will need to be removed to provide the necessary mounting space.
Removing or modifying the factory EVAP system may create diagnostic trouble codes and should be accounted for in your engine-management and tuning setup.
What Comes With the Base Kit
The base fuel-system configuration includes:
- Complete PTFE feed fuel line
- Complete PTFE 6AN return fuel line
- Choice of 6AN or 8AN feed configuration
- Fuel-pressure-regulator connection fitting
- Fuel-rail fittings for your selected configuration
- Required AN fittings for the base fuel system
- Fuel lines assembled and ready for installation
The base kit does NOT include a fuel filter.
The base kit does NOT include a flex-fuel sensor.
The base kit does NOT include a fuel pressure regulator.
The base kit does NOT include a fuel pump.
Ordering Options Explained
Fuel Rail
Select the aftermarket fuel rail installed on your Civic Si.
Different manufacturers use different port designs and fittings, so we use this information to supply the correct connections with your system.
Feed Line Size
Choose:
- 6AN Feed
- 8AN Feed
The return line is always 6AN.
Feed Location
Select how you want the fuel line routed into the fuel rail:
- Side feed - tucked under intake manifold
- Side feed - rear of engine
- Center feed
Both side-feed configurations enter the rail from the USDM passenger side.
For high-horsepower applications, we recommend one of the side-feed configurations.
The rear-of-engine side-feed configuration is not recommended for boosted applications unless adequate heat protection is used.
Fuel Filter Option
The base kit does not include a fuel filter.
Select the Fuel Filter option if you want JBtuned to configure the system with a fuel filter.
Selecting this option changes how the fuel lines are built and adds the components required for the filter installation.
Mounting the fuel-filter bracket requires drilling a mounting hole and installing a rivnut in the mounting location.
Flex-Fuel Sensor Provision
This option does not include the actual flex-fuel sensor.
Selecting the Flex-Fuel Sensor Provision tells us that you plan to install a flex-fuel sensor.
We build the return-line configuration with the correct line arrangement and space for the sensor in the location we have found works best on the 8th Gen Civic Si.
If you need the sensor itself:
Shop JBtuned Genuine Continental Flex-Fuel Sensor
Important Flex-Fuel Electronics Information
Installing a flex-fuel sensor by itself does not make the vehicle flex-fuel capable.
Your engine-management system must be able to read ethanol content and your ECU calibration must be properly configured and tuned for flex-fuel operation.
Depending on the tuning platform being used, a compatible ethanol-content controller, converter, or gauge with the appropriate signal output may be required between the flex-fuel sensor and ECU.
We recommend confirming the required electronics and wiring with your tuner before purchasing the flex-fuel components.
One option we carry is the Innovate MTX-D Ethanol Content / Fuel Temperature Gauge, which can be used as part of a compatible flex-fuel signal setup.
Shop Innovate MTX-D Ethanol Content / Fuel Temperature Gauge
JBtuned Fuel Pump OEM Hanger Upgrade Kit
The JBtuned Fuel Pump Hanger Upgrade option modifies the OEM fuel-pump sending unit so it can properly connect to the upgraded AN fuel system.
The 8th Gen hanger configuration includes components for both the fuel-pump feed and return connection.
The kit includes the required in-tank lines, clamps, feed bulkhead fitting, and return quick-connect components for the selected configuration.
The exact configuration changes depending on which fuel pump you are using, which is why we ask for your fuel-pump selection when ordering.
We strongly recommend this option if your OEM sending unit has not already been properly modified for an aftermarket fuel system.
Regulator Inlet Size
Select the inlet size used by your external fuel pressure regulator.
This information allows us to provide the correct regulator connection fitting.
If you are unsure which size your regulator uses, contact JBtuned before ordering and we can help you identify it.
High Heat Sleeve
The High Heat Sleeve option adds protective heat sleeving to fuel-line sections that may be exposed to elevated temperatures.
We strongly recommend this option for turbocharged builds where lines pass near:
- Turbocharger
- Sidewinder turbo manifold
- Wastegate
- Downpipe
- Other high-temperature exhaust components
Complete Your 8th Gen Civic Si Fuel System
Depending on the components already installed on your vehicle and the options selected above, you may need the following parts to complete your fuel system.
Fuel Pressure Regulator - Required
This system requires an external adjustable fuel pressure regulator.
For most configurations, we recommend the AEM 25-302BK Adjustable Fuel Pressure Regulator.
Shop AEM Adjustable Fuel Pressure Regulator
Fuel Pump
A fuel pump is not included with the base fuel-system kit.
Choose the fuel pump based on your horsepower goal, fuel type, engine combination, and electrical system.
Continental Flex-Fuel Sensor
If you select the Flex-Fuel Sensor Provision, the sensor itself must be purchased separately.
Shop JBtuned Genuine Continental Flex-Fuel Sensor
Flex-Fuel Sensor 6AN Fittings
These quick-connect fittings attach to the Continental flex-fuel sensor and convert the sensor connections for integration into the 6AN fuel system.
Shop Flex-Fuel Sensor Quick-Connect Fittings
JBtuned Flex-Fuel Sensor Mounting Bracket
For a clean sensor installation, JBtuned also offers a dedicated flex-fuel sensor mounting bracket.
Shop JBtuned Flex-Fuel Sensor Mounting Bracket
Innovate MTX-D Ethanol Content / Fuel Temperature Gauge
For builds that require an ethanol-content display and compatible analog-output solution, the Innovate MTX-D provides ethanol-content and fuel-temperature information as part of a flex-fuel installation.
Shop Innovate MTX-D Ethanol Content / Fuel Temperature Gauge
A Typical E85 / Flex-Fuel 8th Gen Civic Si Setup
A complete E85 or flex-fuel FA5/FG2 fuel-system setup may include:
- JBtuned 8th Gen Civic Si Complete Fuel System
- 6AN or 8AN PTFE feed line
- 6AN PTFE return line
- Fuel-filter option
- Flex-fuel sensor provision
- Genuine Continental flex-fuel sensor
- Flex-fuel sensor 6AN fittings
- JBtuned flex-fuel sensor mounting bracket
- Compatible ethanol-content controller / converter
- External adjustable fuel pressure regulator
- Properly sized aftermarket fuel pump
- JBtuned OEM fuel-pump hanger upgrade
- Proper engine management and flex-fuel calibration
Under-Car Fuel-Line Mounting
The current 8th Gen Civic Si installation reuses the factory Honda plastic fuel/brake-line C-clamps underneath the vehicle.
The OEM clamps require minor modification so the larger AN fuel lines fit correctly.
A Dremel or similar tool can be used to carefully open the required portions of the factory clamps.
The original plastic clamps can become brittle with age, so use care during removal and modification.
If replacement OEM clamps are needed, the Honda part number currently used for this application is:
Honda Part #91596-SDA-A01
Installation Notes
- See the product images for fuel-line routing and installation examples.
- The OEM EVAP system must be removed to provide mounting space for the fuel-system components.
- The optional fuel-filter mounting bracket requires drilling and a rivnut for installation.
- Reuse and modify the OEM under-car fuel/brake-line C-clamps.
- Retain the factory firewall heat shields whenever possible.
- Keep all fuel lines properly protected from turbocharger and exhaust heat.
Every modified Civic is slightly different. Turbo manifolds, fuel rails, regulators, intake manifolds, exhaust components, and other modifications can affect fuel-line routing.
If you have an unusual setup or are unsure which options to select, contact JBtuned before ordering and we can help determine the correct configuration.
Professional installation recommended.
