GLOSSARY

[sam2019]

Will be added to willy-nilly as stuff comes up:


ECU - Fundamentally, the engine control unit ECU controls the injection of the fuel and, in petrol engines, the timing of the spark to ignite it. It determines the position of the engine's internals using a Crankshaft Position Sensor so that the injectors and ignition system are activated at precisely the correct time.

Piggyback ECU's are wired to work with the factory ECU. ... Intercept the signal from the sensors before the factory ECU, and modify those signals so the stock ECU is “tricked” into making the vehicle behave the way you want. Example: Powertronic, Power Commander

TPS - A throttle position sensor (TPS) is a sensor used to monitor the air intake of an engine. The sensor is usually located on the butterfly spindle/shaft, so that it can directly monitor the position of the throttle. ... These modern non contact TPS include Hall effect sensors, inductive sensors, magnetoresistive and others.

TB - Throttle body The "equivalent" of the carburetor in an injection engine (not 100% but close enough - google it for more info)

TB/ECU combi - In the latest models the ECU is "hardened" against manipulation, to achieve this it is glued to the TB to allow for inaccessibility of some of the sensors that would otherwise be available for manipulation by so called "piggyback ECUs". BS6/EURO5 and above.

QC quality control. something of questionable repute with RE

RE Royal Enfield, subsidiary of Eicher Motors.

RWHP Rear wheel horse power, measured on a Dynamometer aka Dyno. Often only the acronym HP is used.

BHP Break horse power, measured at the crankshaft

H. or Hitch - short for Hitchcocks - an England based parts supplier for RE 3rd party stuff

The Red Box - A fully programmable replacement ECU for the EFI for the BS4/EURO4 version. The best option to optimize engine performance because piggybacks can only do so much ECU cheating. Not available for the BS6/EURO5 version.

MAF mass air flow sensor. On the Hima its mounted at the top of the Throttle body.

 

[sam2019]

TPS - Extended explanation:

What is a Throttle Position Sensor?​

The throttle position sensor is a vital part of the fuel management system installed on the throttle body. Its primary job is to ensure the correct mixture of fuel and air is delivered through the fuel injection system, through the intake, and into the combustion chamber. Like any other sensor, the TPS is designed to collect data. In this case, it monitors the position of the throttle in relation to the RPM, or how fast the engine turns over. The data collected and signal it produces is sent to the ECU or ECM, which then breaks down the data to change the fuel to air mixture.

There are a few specific ways the TPS can fail such as having a poor electrical connection, being clogged with excessive carbon deposits or other debris, or internal failure of the sensor itself. When the sensor fails it is typically a gradual issue, and when it does, it will display any of these 4 common symptoms:

1. The check engine light illuminates: The check engine light is triggered when an OBD-II trouble code is created and stored in the computer. A failure or gradual failure of the TPS will send an electrical signal to the ECU and activate a code that will trigger the check engine light.
2. Poor fuel economy: When the TPS is not working correctly, the air/fuel ratio will likely result in a rich condition where more fuel is being burned than it should. This can result is more fuel consumption.
3. Inconsistent engine idle: In some cases, a damaged TPS will result in an inconsistent engine idle speed that either moves too slowly or possibly stalls.
4. Lack of power accelerating: Its also common for reduced engine performance (acceleration) to occur when the TPS is damaged.

 

[sam2019]

Head Porting:

What is head porting and polishing and how does it work?Porting involves shaping and/or polishing the intake port openings, the inside of the ports, the exhaust ports, the bowl area below the valve seats and the combustion chambers to increase the head's ability to flow air.

 

[sam2019]

Performance camshaft - The camshaft in general functions to open/close the inlet and outlet valves. The LS410 engine (and its modern derivative the 440) uses an overhead camshaft connected to the crank by a timing chain.
The LS410 stock cam also uses a de-compressor that allows for easier turning of the engine when starting up. All known performance cams lack this de-compressor (but starting still works).
There are various manufacturers of performance cams all of which change the time of opening the inlet and the depth of opening it thereby allowing for more fuel to enter the chamber. To a degree they can also influence the timing of the opening.
Not all cams are made the same and some have quality issues from the start. Because it is quite work intensive to generate an optimal profile for a given engine companies with a lot of experience and the needed tools (like a dyno) generate better results. In our experience the best results can be had with KENT cams made in Britain and sold by Hitchcocks. Our HT-b is basically a clone of that cam.