Royal Flush
4-bbl TBI system with built-in CDI for classic engines up to 650 hp




































Royal Flush 2 Fuel Kits
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Kit Types Explained
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Save 5% automatically when you purchase a Fuel Kit, Top End Kit, or Master Kit!
- 1. Standalone Kits
Perfect if you already have a high pressure fuel system (43 PSI+) and want to use your stock ignition or if you already have an aftermarket distributor. (Note that a distributor must be locked out to run timing control.)
- Includes the following:
- Throttle body
- ECU
- Handheld or Bluetooth Module
- Full Harness
- Sensors
- Accessories
- 2. Fuel Kits
Perfect if you want to use your stock ignition or if you already have an aftermarket distributor. (Note that a distributor must be locked out to run timing control.)
- Includes the following:
- A complete Standalone Kit
- A Fuel Delivery System of your choosing
- 3. Top End Kits
Perfect if you already have a high pressure fuel system (43 PSI+) and want to run timing control.
- Includes the following:
- A complete Standalone Kit
- A Magnetic Distributor of your choosing
- An AC2008 Ignition Coil
- 4. Master Kits
These include everything you need to go from carb to EFI and run timing control.
- Includes the following:
- A complete Standalone Kit
- A Fuel Delivery System of your choosing
- A Magnetic Distributor of your choosing
- An AC2008 Ignition Coil
The Royal Flush 2 is a 4-bbl throttle body EFI system with integrated CDI for classic engines. Aces is the only EFI manufacturer to produce integrated Capacitive Discharge Ignition (CDI) setups: no costly additional purchases Whether you're running high compression, forced induction, or aggressive racing setups, the Royal Flush 2’s high-voltage CDI system ensures maximum power and efficiency.
Why CDI?
Unlike traditional EFI systems that rely on weaker inductive ignition, Royal Flush 2’s CDI system produces a hotter, more consistent spark that burns fuel more efficiently, leading to:
- Superior combustion in high-boost or high-compression applications
- Increased power and throttle response
- Reduced misfires and improved fuel efficiency
Total Control for Performance Builds
Just like our Killshot system, the Royal Flush 2 EFI/CDI works with most classic engines with a 4150 intake flange. But what sets Royal Flush 2 apart is its built-in CDI technology and racing-grade features:
- Integrated Digital CDI – Produces 150mJ spark energy output for maximum ignition performance
- Massive Voltage Output – Primary voltage: 450-530V / Secondary voltage: 50,000V
- 2-Stage Rev Limiter – Set a max RPM limit for engine protection, plus launch control for optimal starts
- Burnout Mode – Holds RPM at a set limit for consistent, controlled burnouts
Core Features
- Self-learning and full tuning capability
- Expanded 31 x 31 tuning tables
- Integrated digital CDI with 150mj spark energy output
- 2-stage Rev limiter setting for max RPM, launch control, and burn out
- 32-bit software (OEM standard) that manages input/output signals, voltage, and RPM faster and more consistently than competitors
- Easy setup and monitoring with your choice of bluetooth module or HD handheld
- Integrated coil driver for ignition timing control (when using Aces’ coil and distributor)
- Simple calibration wizard for initial setup- no laptop tuning required.
- Dual fan control
- Step retard for nitrous control
- Boost compatibility right out of the box, with boost control coming soon
- Free laptop software available for pro applications
- Compatible with all Aces’ handhelds, dashes, and modules
- Dual 4.9 WBO2 sensors
From street builds to high-boost race cars, Royal Flush 2 EFI/CDI is the ultimate all-in-one ignition and fuel control solution. No need for a separate CDI box—Aces EFI is the only company to offer EFI and CDI in one ECU. If you’re serious about performance, The Royal Flush 2 is the system you need!

Product Info
Overview
The Royal Flush 2 is a 4-bbl throttle body EFI system with integrated CDI for classic engines. Aces is the only EFI manufacturer to produce integrated Capacitive Discharge Ignition (CDI) setups: no costly additional purchases Whether you're running high compression, forced induction, or aggressive racing setups, the Royal Flush 2’s high-voltage CDI system ensures maximum power and efficiency.
Why CDI?
Unlike traditional EFI systems that rely on weaker inductive ignition, Royal Flush 2’s CDI system produces a hotter, more consistent spark that burns fuel more efficiently, leading to:
- Superior combustion in high-boost or high-compression applications
- Increased power and throttle response
- Reduced misfires and improved fuel efficiency
Total Control for Performance Builds
Just like our Killshot system, the Royal Flush 2 EFI/CDI works with most classic engines with a 4150 intake flange. But what sets Royal Flush 2 apart is its built-in CDI technology and racing-grade features:
- Integrated Digital CDI – Produces 150mJ spark energy output for maximum ignition performance
- Massive Voltage Output – Primary voltage: 450-530V / Secondary voltage: 50,000V
- 2-Stage Rev Limiter – Set a max RPM limit for engine protection, plus launch control for optimal starts
- Burnout Mode – Holds RPM at a set limit for consistent, controlled burnouts
Core Features
- Self-learning and full tuning capability
- Expanded 31 x 31 tuning tables
- Integrated digital CDI with 150mj spark energy output
- 2-stage Rev limiter setting for max RPM, launch control, and burn out
- 32-bit software (OEM standard) that manages input/output signals, voltage, and RPM faster and more consistently than competitors
- Easy setup and monitoring with your choice of bluetooth module or HD handheld
- Integrated coil driver for ignition timing control (when using Aces’ coil and distributor)
- Simple calibration wizard for initial setup- no laptop tuning required.
- Dual fan control
- Step retard for nitrous control
- Boost compatibility right out of the box, with boost control coming soon
- Free laptop software available for pro applications
- Compatible with all Aces’ handhelds, dashes, and modules
- Dual 4.9 WBO2 sensors
From street builds to high-boost race cars, Royal Flush 2 EFI/CDI is the ultimate all-in-one ignition and fuel control solution. No need for a separate CDI box—Aces EFI is the only company to offer EFI and CDI in one ECU. If you’re serious about performance, The Royal Flush 2 is the system you need!
Specs
Royal Flush 2 Fuel Kits Specifications
Additional specs are not currently listed for this product.
Resource Documents
For additional manuals, diagrams, measurements, and more, check out our documents page in our Resource Center by clicking here.
What's in the box?
The Royal Flush 2 is a 4-bbl throttle body EFI system with integrated CDI for classic engines. Aces is the only EFI manufacturer to produce integrated Capacitive Discharge Ignition (CDI) setups: no costly additional purchases Whether you're running high compression, forced induction, or aggressive racing setups, the Royal Flush 2’s high-voltage CDI system ensures maximum power and efficiency.
Why CDI?
Unlike traditional EFI systems that rely on weaker inductive ignition, Royal Flush 2’s CDI system produces a hotter, more consistent spark that burns fuel more efficiently, leading to:
- Superior combustion in high-boost or high-compression applications
- Increased power and throttle response
- Reduced misfires and improved fuel efficiency
Total Control for Performance Builds
Just like our Killshot system, the Royal Flush 2 EFI/CDI works with most classic engines with a 4150 intake flange. But what sets Royal Flush 2 apart is its built-in CDI technology and racing-grade features:
- Integrated Digital CDI – Produces 150mJ spark energy output for maximum ignition performance
- Massive Voltage Output – Primary voltage: 450-530V / Secondary voltage: 50,000V
- 2-Stage Rev Limiter – Set a max RPM limit for engine protection, plus launch control for optimal starts
- Burnout Mode – Holds RPM at a set limit for consistent, controlled burnouts
Core Features
- Self-learning and full tuning capability
- Expanded 31 x 31 tuning tables
- Integrated digital CDI with 150mj spark energy output
- 2-stage Rev limiter setting for max RPM, launch control, and burn out
- 32-bit software (OEM standard) that manages input/output signals, voltage, and RPM faster and more consistently than competitors
- Easy setup and monitoring with your choice of bluetooth module or HD handheld
- Integrated coil driver for ignition timing control (when using Aces’ coil and distributor)
- Simple calibration wizard for initial setup- no laptop tuning required.
- Dual fan control
- Step retard for nitrous control
- Boost compatibility right out of the box, with boost control coming soon
- Free laptop software available for pro applications
- Compatible with all Aces’ handhelds, dashes, and modules
- Dual 4.9 WBO2 sensors
From street builds to high-boost race cars, Royal Flush 2 EFI/CDI is the ultimate all-in-one ignition and fuel control solution. No need for a separate CDI box—Aces EFI is the only company to offer EFI and CDI in one ECU. If you’re serious about performance, The Royal Flush 2 is the system you need!
Royal Flush 2 Fuel Kits Specifications
Additional specs are not currently listed for this product.
For additional manuals, diagrams, measurements, and more, check out our documents page in our Resource Center by clicking here.
Fuel Kit Feature
(Fuel) Pump Up the Jam
Each Master Kit will come with a fuel system of your choosing. You can scroll down to read more about the available options below.

Command Center 2
A surge tank system that allows you to keep your mechanical pump in place. A better option for classic trucks or other vehicles where the tank is hard to access.

Tight-fit In Tank Pump Module
An in-tank fuel pump module available with or without PTFE hose.
Requires a return line to the tank.

Tank Conversion Fuel Pump Module
An in-tank fuel pump module with an internal regulator. Ideal for fuel cells.
Does not require a return line to the tank.
How do I set up and program my system?
Interface Options
Our EFI systems are self-learning for most stock-to-mild engine builds. You’ll use one of the included interface modules (depending on the option selected at purchase) to complete the initial setup and make adjustments on the fly. The startup wizard will prompt you with 6–12 setup questions, after which the self-learn feature takes over.
Additional fine-tuning may be required later, depending on your specific build.

5" Handheld (3rd Gen)
- Capacitive touch screen
- 64-bit processor
- 1280x720 resolution
- Cable connection via main harness

8" Handheld (1st Gen)
- Capacitive touch screen
- 64-bit processor
- 1280x800 resolution
- Wifi chip for software updates via the internet
- Cable connection via main harness
Most common questions
Quick answers to our most common queries for this product.
The Royal Flush 2 Fuel Kits are designed to work with any classic 4, 6, or 8 cylinder engine that is under 650 hp, uses a 4150 style flange, and has a fuel system rated for EFI (43 PSI).
The self learn will work for most stock-mild builds, while some mild and more advanced builds may require manual tuning.
The Royal Flush 2 Fuel Kits are designed to work with most stock or aftermarket ignition components. They will work with most tachometers and are compatible with Dakota Digital dashes using their Aces BIM Module (BIM-EFI-1).
Self-tuning is a common term used among aftermarket EFI companies, but we prefer the term "self-learning" as that is more accurate, even for our competitors who advertise "self-tuning."
Our systems are designed to self-learn the fuel MAPs and work best for stock-mild builds. Some mild builds and anything beyond that would require manual tuning, of which the system is fully capable. Additional features like nitrous and boost are also considered beyond stock and require manual adjustments to enable and configure these kinds of features.
Yes! You can make many changes using the Bluetooth or handheld interface, and we also offer a free PC app for more advanced tuning.
The Royal Flush 2 Fuel Kits can work with standard stock or aftermarket ignition components, but if you want to run timing control, it will need either a magnetic pickup distributor that has been locked out or a Hall Effect distributor. You will also need to make sure that your fuel delivery system can support 43-58 PSI. Whether or not you need a return line will depend on your fuel delivery system and if the regulator is inside or outside the tank. Whether or not you need to replace your tank will depend on which fuel delivery system you choose. We offer complete Master Kits for each EFI system that come with new ignition components and a fuel delivery system. You can visit the Royal Flush Master Kits page here.
Yes to both! The Royal Flush 2 Fuel Kits are compatible with both blow-through, draw-through, and nitrous applications and are also compatible with E85 Fuels. The Royal Flush 2 Fuel Kits' MAP sensor can be scaled for up to 26 lbs of boost and can be set to retard timing.
Note that for boost, the system is compatible, but cannot control the boost. You will need to use a separate controller for things such as wastegate control or solenoid activation. Use of these features will require manual tuning.















