Price: $399

If you’re new to NepTune, check out our Video Tutorials on how to get started.


This package includes one Demon unit (Pictured above) and one software license for the NepTune RTP software.

*JDM ECUs will still need to use the original Demon unit for fitment. Make sure to tell your dealer.


 Download For Windows Now, XP through Windows 10
 Download For Mac OS X Now, Up To 10.14



Enjoy access to these great features of the NepTune RTP software (Pictured Below):

Beautiful 3D Beveled interface.

User Friendly Toolbars with the options you need most.

Real-Time Datalogging Of Sensor Data, Inputs, Outputs, and ECU Data.

On Board Logging With Lossless Compression To Allow 3 To 5 Times The Regular Amount Of Data To Be Recorded. Offers Up To 12 Hours Of Datalogging Time With Compression Enabled.

Datalog Playback, Save, and Export to CSV.

Datalog Trimming.

Datalog Commenting For Later Review or Sharing With A Tuner.

Graphing Of Sensor Information With Real-Time Values and Live Scrub (Dragging with mouse).

Live Graphing Of Real-Time Sensor Trends.

Direct Serial Logging From LC-1, LC-2, LM-1, LM-2 (LM-2 USB Is Fully Supported on Windows), and PLX Wideband Products.

Map Trace and Lambda Trace.

24×24 Ignition and Fuel Maps For Precise Tuning.

Manage And Switch Between Up To 3 Separate Tunes (Demon 1 Only). Each Separate Tune Includes A Fully Separate Set Of Maps and Parameters.

Dual Tables For Low/High Boost, Different Fuels, or Alpha-N (ITB) Tuning.

Easy Injector Sizing.

Fuel Trims for Cranking, TPS Tip-In, Post Start, and Individual Cylinders.

Rev Limiter with Fuel Cut, Ignition Cut, or Both.

Rev Limits Per Gear.

Launch Control (2-step) With Anti-Lag.

Full-Throttle Shift.

Use The Check Engine Light As A Shiftlight With Different RPM Settings Per Gear.

Idle Adjustments for Idle Speed, Idle Speed vs ECT, and Idle Ignition Corrections.

Air Temp Corrections.

Water Temp Corrections.

Gear Based Fuel and Ignition Corrections.

Sensor Adjustments For Altering Fuel, Ignition, And PWM Duty Cycle Based On An Analog Input. This Means Support For Flex Fuel Sensors, Traction Control, PWM Boost Gain Control, And Other Specialized Features.

Access To Many Other Stock Fuel and Ignition Adjustments.

PWM Boost Control With Simple, Boost By Gear, and Gear vs RPM Modes.

Quad Stage Boost Control.

Adjustable Prime Duration At Key On.

Overheat Protection.

Closed Loop Control With Selectable O2 Input, Conditions, and Wideband Support.

Anti-Theft feature requires inputs or a code to be entered with TPS and Brake pedal. Also has a valet/fallback mode with adjustable rev limit.

2 Multi-purpose Outputs With Fuel and Ignition Adjustments.

1 Multi-purpose Output With Multiple Output Settings Based On MPH.

9 (Demon) or 8 (Demon II) Programmable Analog Inputs For Extra Sensors. 4 Can Be Used Through The ECU For Closed Loop And Other Features.

And A Lot More!

Let’s compare to the other three best known systems out there.

What makes NepTune a better option than S300? NepTune has more usable features and comparable features that exceed the configurability of a S300 (Like Anti-Theft, Up to 12 hours of on board logging with better start and stop parameters, access to more ignition corrections and the ability to disable corrections completely, and live graphing just to name a few) at a much lower price because we don’t have as much overhead. We don’t sacrifice quality because we have a lower price either… In fact everything is thoroughly tested and stable before being released to the public and updates to improve usability occur regularly. NepTune offers the best support in the industry, and we’ll make sure you have the best experience possible with our system.

What makes NepTune a better option than Crome? The list of features NepTune has that Crome does not is endless, and at $44 more than a Crome Pro Tuning Package (Ostrich-$175, Hulog-$30, and Crome Pro-$150) it’s worth it! Complete ignition control, better datalogging, datalog graphing, live graphing, PWM boost control, Anti-Theft, and a huge list of other features can really make the difference when it comes to tuning a vehicle. Best of all our features work properly so you won’t struggle with tracking down bugs.

What makes NepTune a better option than eCtune? While NepTune and eCtune have a very comparable price and feature list (They have a few we don’t have… and we have a few they don’t have yet, like Anti-Theft, on board logging, and proper closed loop wideband support), NepTune has been around longer and is more thoroughly tested before releases. Best of all it shows. NepTune’s features are rock solid, our support is second to none, and our support forum is not constantly full of bug reports. We also don’t force you to update your software if you’re happy with the current version.

Feel free to visit our forum or email us directly with any questions you have.

Download the software today to take a look!

RTP Features
On Board Datalogging (Demon RTP) Up to 12 hours of recording time with compression enabled
Real-Time Datalogging Access to many data points in real-time
Real-Time Tuning Live tuning capabilities via NepTune RTP Software with full control of all parameters and maps
Wireless Capability With bluetooth Add-On Module
*Fuel/Ignition Maps
Primary and Secondary Maps Primary and Secondary low and high cam fuel and ignition maps. 8 maps total. 24 load breakpoints by 24 rpm breakpoints for precise tuning. Low and high cam both can be scaled to go to 11000 and above
*Rev Limits/VTEC
Rev Limits Per Gear
Fuel And/Or Ignition Cut
High and Low Cam Rev Limits Low cam rev limit doubles as a cold limit
High and Low Load VTEC Engagement RPMs Separate engagement RPMs for low and high load
TPS threshold decides low/high load This option decides whether to use the low or high load engagement RPM
Minimum load for engagement This option only allows VTEC to engage above the specified load
Disengage below minimum load When VTEC is engaged this option determines whether or not to disengage below the minimum load or disengage below the set engagement RPM
Minimum Speed
Minimum ECT
VTEC Disable For Non-VTEC setups
VTEC Speed Threshold Disable Allows VTEC to activate at launch or on setups without a VSS
VTEC Temperature Threshold Disable Allows VTEC to activate while the car isn’t fully warmed up
VTEC Pressure Disable For setups without a VTEC Pressure switch
VTEC Error Check Disable Only suggested for race vehicles
New and old injector size Can be used with the overall trim to rescale for new injector sizes
Overall Fuel Trim Globally applied fuel correction
TPS Tip-In Fuel Trim Correction to accurately tune TPS Tip-In for different size injectors and different setups
Cranking Fuel Trim Fuel correction for Raw Cranking Fuel Maps
Post Start Fuel Trim Correction for fuel delivered immediately after startup
Adjustable ECT vs Raw Cranking Fuel Maps Used to determine how much fuel is used to start the engine
Adjustable ECT vs Fuel Enrichment Maps Used for cold start enrichment
Adjustable ECT vs Ignition Correction Maps Used for cold start correction
Adjustable IAT vs Fuel Enrichment Maps Complete fuel correction for weather changes
Adjustable IAT vs Ignition Correction Maps Ignition correction for intake temperature
Adjustable Gear Based Fuel Enrichment Maps Allows balancing of air/fuel ratios between different gears
Adjustable Gear Based Ignition Correction Maps Can be used as an aid for traction
Adjustable Idle Ignition Corrections
Adjustable Ignition Limitations For Ignition Maps
Adjustable Ignition Dwell Control
Adjustable Tip-In Ignition Corrections
Adjustable Individual Cylinder Fuel Trim Allows adjustments to fuel to obtain equal individual cylinder EGTs and more
Injector Battery Compensation Allows adjustments to fuel based on battery voltage
Target Idle
ECT vs Target Idle maps Fully adjustable ECT and target idle values for the startup idle maps
IACV Duty Cycle Adjustment Allows adjustment of IACV duty cycle to help you reach your target RPM
*AC Cutoff
Above RPM
Above TPS threshold
Idle Recovery Disengages the AC clutch below this RPM to help regain control over a low idle
Activation by MPH No need for a clutch switch!
Activation by TPS threshold Rev until any RPM you choose, cross the TPS threshold and it holds that RPM
Activation by switch/clutch switch Can be used to turn 2-step on/off or used as a clutch input
MPH threshold for 2-step Can help limit you off the line to keep traction under control
Ignition Retard/Fuel Enrichment Allows you to build boost off the 2-step
TPS threshold for retard/enrichment Allows you to pre-stage on the 2-step before building boost
Full Throttle Shift Holds the target RPM during shifts. Requires use of a clutch input
Selectable clutch switch input Several inputs to choose from to fit what’s available
*Outputs (2)
Activation Input Not required for activation but can be used as an on/off switch
Activation Output Several outputs to choose from
Minimum RPM
Maximum RPM
Minimum Load
Maximum Load
Minimum speed
Minimum Throttle Position
Minimum Intake Air Temperature
Maximum Intake Air Temperature
Minimum Engine Coolant Temperature
Maximum Engine Coolant Temperature
Ignition Retard By RPM Retards ignition while activated
Fuel Enrichment By RPM Adds fuel while activated
Switch maps on activation Ability to use secondary maps to completely tune for nitrous
Disable on FTL/FTS
Disable if MIL code
*Boost Control For use with dual, tri, and quad stage boost controllers
Activation Input Not required for activation but can be used as an on/off switch
Activation Output Selectable outputs for each stage of boost
Minimum RPM
Minimum speed
Minimum Throttle Position
Boost Cut Keeps you from going over a determined safe level of boost
PWM Based Boost Control
Variable Frequency For Multiple Solenoid Types
Quick Spool Duty Cycle And Load Setting Allows you to hold a specific duty cycle until the load condition
Set Duty
Boost By Gear
Boost By Gear vs RPM
Low/Hi Boost Switch Input
*Fan Control Allows full control of what temperature the fan is activated
Activation Output
Minimum Engine Coolant Temperature
Maximum Speed
*Switch Maps
Flexible Dual Map Setup Primary and secondary maps can be setup to use MAP or TPS as load reference, Load and RPM breakpoints can be completely different. Can be used for extending load points/rpm breakpoints, alpha-n scaling, pump/race tunes, etc
Activation Input Not required for activation but can be used as a switch between the different maps
Minimum RPM
Minimum Load Optional setting, can be disabled. For use with maps extending onto the secondary maps
Minimum Throttle Position Optional setting, can be disabled. For use with Alpha-N scaling for ITB tuning
Use High Cam Maps Only Can be used to tune VTEC setups using one set of maps only
Required Inputs Can require multiple inputs to be set or unset
Optionally Required Code Code is entered via presses of the TPS and Brake Pedal
Valet/Fallback Mode Allows vehicle to start with adjustable rev limit as valet or fallback for Anti-Theft
*Closed Loop Control
Full Wideband Support Works with full 0-5v scale
Target O2 Voltage Can be changed to set target closed loop a/f
Disable Closed Loop Above Load Beneficial to small turbo and supercharged setups that build boost even at partial throttle
Other Conditions Conditions for ECT, IAT, and RPM
Adjustable Voltage Error Disables closed loop in the event of sensor failure
Disable Closed Loop Error Option
RPM vs TPS Threshold Gives access to the maps that govern the stock closed loop routines
Disable Closed Loop Option Disables closed loop completely
Disable Open Loop Lookup Table Option Disables enrichments from the open loop lookup table
ECT Threshold For Open Loop Table Use The temperature that the Open Loop Lookup Table starts being applied
*Sensors and more
Disable Knock Sensor
Disable Injector Test Circuitry Many EDM/JDM ECUs do not have this
Disable BARO Sensor Many EDM/JDM ECUs do not have this
Disable ELD
Disable O2 Heater Allows use of 1 wire O2 sensor or no O2 sensor if Closed Loop is disabled
Disable IACV Error For vehicles that don’t have an IACV hooked up
Disable IAB
IAB Activation RPM
MAP Sensor Support Support for a wide range of map sensors from stock up to 5 bar and beyond via custom map settings
Sensor Adjustments Allows adjustment of fuel, ignition, and PWM duty cycle based on a 0-5v analog input.
9 Programmable Analog Inputs Allows logging of any 0-5v sensor. Breakpoints are fully configurable.
Service Input Allows you to change the service input to any other input or none at all. This frees up the service connector to be used as a switch for one of the other options. Codes are also shown with the car off key in the on position with the throttle over 65%
Clear Codes With The Brake Pedal If you wish to clear codes in memory you can press the brake pedal while checking your codes to clear them from memory
Adjustable Fuel Prime Time
MIL Shiftlight Per Gear Activates the MIL at the specified RPM
Adjustable Deceleration Fuel Cut Load, Speed, and TPS dependent
Lock Ignition Timing Lock ignition steady to set ignition timing
Injector Kill To kill the engine without keying off