Tuning
Basic Concepts of Honda Engine Management
An introductory guide to electronic engine management concepts for Honda enthusiasts, covering air, fuel, spark, and sen...
Turbo Compressor Map
Guide to reading and interpreting turbocharger compressor maps for matching turbochargers to Honda engine performance go...
Honda ECU Serial Datalogging (`CN2` TTL Header)
Learn how Honda OBD1 ECUs communicate with tuning laptops via serial TTL signals (CN2 header), including pinouts, settin...
Introduction to ECU Chipping
A comprehensive guide to the hardware and software fundamentals of socketing and chipping OBD0 and OBD1 Honda ECUs.
USB-to-TTL Serial Converter Guide (`FTDI` & CP2102)
How to configure and troubleshoot USB-to-TTL serial converters (such as FTDI or CP2102 chips) for reliable ECU dataloggi...
Parameters Window Overview
A practical overview of the parameters window in Hondata software, explaining which ECU settings it exposes and how it f...
Data Link Connector (DLC) Communication Protocols
Technical specifications of the Honda OBD1 Data Link Connector (DLC) communication protocol, voltage levels, capacitance...
Calibration Window Overview
How the calibration window is organized in Hondata tuning software, including parameter groups, change indicators, right...
MAP Sensor Parameters
How Hondata MAP sensor parameters work, including sensor selection, scalar and offset values, boost limits, and safe sen...
Multiprocessor Communication Protocols
An overview of 8051-based multiprocessor communication protocols, detailing the use of 9-bit serial modes for selective...
Modifying Target Idle RPM in OBD0 PM7 ECUs
Learn how to modify the target idle RPM in OBD0 PM7 ECU ROMs by locating and adjusting the hex idle target string.
OBD0 Engine Control Units (1988–1991)
OBD0 refers to the non-standardized engine control units used in Honda and Acura vehicles from 1988–1991, primarily feat...
Crome ROM Tuning FAQ
Frequently asked questions about Crome, a popular ROM editing and tuning software for OBD1 Honda ECUs.
Ghetto Dyne Tuning Platform
Historical overview of the Ghetto Dyne tuning platform and its transition to modern ECU tuning software.
OBD2K ECU Standard
Technical overview of the OBD2K ECU standard used in 2001+ Honda K-series engine management systems.
Turbocharger Fundamentals
A turbocharger is a centrifugal compressor that increases intake pressure in an internal-combustion engine, powered by a...
Zero Insertion Force (ZIF) Sockets for ECU Tuning
A guide to Zero Insertion Force (ZIF) sockets for ECU tuning, covering installation considerations and hardware selectio...
JDM P30 D12 Analog-Input Modification
Technical guide for modifying the JDM P30 OBD1 ECU to enable 0-5 V analog signal logging via the D12 input.
High-Resolution (Hi-Res) P72 ROM Specifications
Technical reference and memory map offset guide for the John Cui High-Resolution (Hi-Res) P72 custom ROM modification, e...
Uber P72 ROM Map
Technical reference for RAM and ROM address offsets specific to the UberData custom ROM codebase for OBD1 P72 ECUs.
Crome JavaScript Scripting API
Technical reference for the legacy Crome ROM editor JavaScript API used for developing scripts, ROM handlers, and plug-i...
Dual-Map ROM Tuning for Honda ECUs
An overview of dual-map ROM configurations for Honda ECUs, enabling switchable engine tuning profiles for different fuel...
EA (EA Prime) Pin Functionality
The EA (EA Prime) pin on the MCU determines whether the ECU executes code from internal ROM or an external ROM chip, ess...
Electronic Boost Controller Fundamentals
An Electronic Boost Controller (EBC) uses a solenoid and logic controller to regulate wastegate actuation, allowing for...
Fuel Cut Operation and Theory
A fuel cut disables fuel delivery to the engine, typically triggered by rev limiters, launch control, or boost cut routi...
Introduction to TurboEdit (OBD0 Honda Tuning)
An introduction to TurboEdit, the open-source ROM editing and tuning software for OBD0 Honda ECUs (PM6/PM7 codebases).
OBD1 8-bit MAP Calibration in Millibars
Technical reference for OBD1 P72/P75 MAP-byte conversion formulas, calibration values, and voltage scaling.
OBD1 ECU J1 Jumper Configuration
The J1 jumper on OBD1 ECUs controls the EA pin state, determining whether the MCU executes code from the internal progra...
OBD2A
OBD2A refers to the OBD2 ECUs made from 9698 Library.OBD2A moved from Library.OBD2AECU on 31 Mar 2004 18:21 by Home.blun...
Pocket Programmer 2 Technical Overview
Technical overview and evaluation of the Xtronics Pocket Programmer 2, a common EPROM burner used for ECU chip tuning.
Read Only Memory (ROM) Architecture
An overview of Read Only Memory (ROM) architecture and its role in Honda engine control unit (ECU) firmware storage.
Turbocharger Wastegate Operation
A wastegate regulates turbocharger boost pressure by bypassing exhaust gas around the turbine wheel. Learn how this mech...
UberData Tuning FAQ
Archived setup and tuning FAQ for the legacy UberData OBD1 Honda ROM editor.
Understanding Dec At Addy
An explanation of the Dec At Addy conversion process, which translates hexadecimal values stored at specific ECU memory...
VTEC Crossover Point Calibration
The VTEC crossover point is the specific engine RPM at which the ECU activates the VTEC solenoid to transition from low-...
DIY Dual-ROM Setup (27C512 Jumper Switch)
Hardware modification guide to creating a dual-ROM setup using a 27C512 EPROM and a toggle switch to select between two...
Exhaust Gas Temperature (EGT) Sensor Overview
An overview of Exhaust Gas Temperature (EGT) sensors and their role in monitoring ignition timing and engine health duri...
Full-Duplex Datalogging & the `J12` Jumper
Explains the difference between half-duplex and full-duplex serial communication on OBD1 Honda ECUs and why removing the...
Logging an External 0-5 V Sensor via P30 D12
Technical guide for utilizing the undocumented D12 analog input on USDM OBD1 P30 ECUs for 0-5 V external sensor logging.
Proposed Datalogging & RTP Protocol
Technical specification of the proposed high-speed, stream-based custom datalogging and Real-Time Programming (RTP) prot...
Remove A Knock Sensor
Removing the knock detection is simple: Resolder R118 and R119 into R142, 143. Then, Remove R101 (optional).
Atmospheric Pressure (PA) Sensor Reference
The atmospheric pressure (PA) sensor measures ambient air pressure to adjust fuel mixtures for altitude and weather-rela...
Crome ROM Editor Overview
Crome is a ROM editor for Honda ECUs that supports JavaScript-based scripting for custom feature implementation and exte...
DAC
Digital to Analog Converter. the process of taking a digital value and converting it to an analog signal of some variety...
Disabling VTEC VSS Check on P28 ECUs
Technical guide for disabling the Vehicle Speed Sensor (VSS) check in the VTEC engagement routine for Honda P28 OBD1 ECU...
DIY Easy-RTP v1.0 Build and Installation Guide
Technical assembly guide and installation notes for the DIY Easy-RTP v1.0 EPROM emulator board for OBD0 and OBD1 Honda E...
Dual Runner Intake Manifold Operation
Understand the operation and tuning principles of Honda dual-runner intake manifolds, including IAB (Intake Air Bypass)...
ECU Nitrous Control Implementation
Implementing ECU-based nitrous solenoid activation to enable dynamic fuel and ignition map switching.
Electronic Part Supplier Reference
A curated list of reliable electronic component suppliers and specific part references for ECU modification and repair.
Honda ECU Launch Control (Two-Step) Implementation
Technical explanation of launch control "two-step" rev limiter features in Honda ECUs, enabling consistent standing star...
Honda MAP Sensor Voltage Calibration Equations
A technical reference for calculating manifold absolute pressure (MAP) sensor voltage outputs using linear modeling equa...
Honda PT6 and PK3 ECU Technical Specifications
Technical reference for Honda PT6 and PK3 series ECUs, detailing MCU specifications and PROM configurations for OBD-era...
Ideal Gas Law in Speed-Density Tuning
Application of the Ideal Gas Law in Honda speed-density engine management systems for calculating fuel requirements base...
Installing and Configuring the Add Extra Features Plugin for Crome
A technical guide for installing and applying the Add Extra Features plugin in Crome to enable advanced OBD1 tuning func...
OBD1 Honda ECU Routine Reference
Technical reference for OBD1 Honda ECU routines, including documentation on I/O operations and specific A/C control logi...
P13 JDM ECU Memory Map
Technical reference for P13 JDM ECU memory mapping, including RAM locations and ROM-based rev limit calculations.
Piggyback Engine Management Controllers
A piggyback controller is an aftermarket device that intercepts and modifies engine sensor signals before they reach the...
PJ0 ECU Technical Reference
Technical overview of the PJ0 ECU used in 1986–1989 Honda Accord and Prelude models, covering hardware revisions and reg...
ROM Editor Overview
ROM editors provide a graphical interface for modifying ECU calibration data, allowing users to adjust engine parameters...
Technical Considerations for Retrofitting Knock Sensors
Technical warning regarding knock sensor installation on non-equipped engines, citing cylinder bore and knock board cali...