Glossary Take II

[elhigh]

Man-Miles Per Gallon = MMPG.

Number of people in the car x miles per gallon = MMPG.

Driving for maximum economy is great. Doing it with more people aboard is even better.

[ijames]

I've seen the other emoticons on other boards, but what do and mean? I've never run across them before.

[Joggernot]

Sometimes it means we're making slow progress...

[Focus-Ak]

Here are (1) a suggestion and (2) a compiled list of the technical acronyms from this topic thread.

MY SUGGESTION: In the constant top-of-page menu on this, Glossary should link to a separate page with the acronym decoder below. That page should also include a link to this topic. It is too cumbersome to dig through this topic to find a cryptic acronym, and the EcoModder site is so acronym-heavy that this is a real barrier for newbies like me.

COMPILED ACRONYM LIST (technical ones only):

A = Area (projected frontal area). Looking at a vehicle directly head on (or directly from the rear), A is the area within an outline traced around the vehicle's extremity. Used for calculating aerodynamic drag. See also = Cd, CdA.

A-B-A = Preferred test method for evaluating modifications/driving techniques under "as controlled as possible" conditions. (A) baseline data is gathered immediately before a change; (B) a change is introduced and further data is gathered; (A) the change is immediately removed and additional data is taken again under identical conditions. Identical results in the two "A" stages supports the quality of the "B" data. Without a second "A" data set, "B" data should be viewed more skeptically.

A/C = Air conditioning

BSFC = Brake Specific Fuel Consumption. Measurement of how much fuel is required to produce a specific amount of power from a given engine. Every engine has an efficiency "BSFC island" or "sweet spot" where a under specific load and engine speed (RPM) it uses the least amount of fuel per unit of power produced.

CAI = Cold Air Intake. (Generally not thought to be an aid to fuel effiency = more pumping losses are encountered moving denser air through an engine.)

Cd = Coefficient of Drag. A dimensionless number describing the aerodynamic drag of a body - e.g. the Honda Insight's Cd is 0.25; basjoos' AeroCivic is approximately 0.19. Sometimes expressed as Cx or Cw. (See also "A".)

CdA = Coefficient of Drag times frontal area. Total drag is the product of both the shape and size of an object.

CIE = compression ignition engine., SIE spark ignition engine

CODFISH = Coast On Demand Forced Ignition Shutoff. Same as "EOC" (Engine Off Coasting). A joke acronym made up to poke fun at the ridiculous tendency of hypermilers to create and use an excessive number of acronyms/initialisms. Unfortunately, the person who made it up has since stopped participating in fuel efficiency forums, and taken his sense of humour elsewhere.

CSL = Cautionary Speed Limit

CVT = Actually stands for Continuously Variable Transmission

DFCO = Deceleration Fuel Cut Off, a condition where fuel injection stops when the accelerator is released and engine speed is above a target determined by the computer. The engine continues turning via the transmission, driven by the vehicle's momentum. Once below the threshold engine speed (1300-1500ish rpm), fuel injection resumes allowing the engine to continue to run.

DWB = Driving without using brakes

DWL = Driving With Load. I prefer to call it "target driving" because it essentially means you pick a target MPG figure to maintain, and you adjust the accelerator pedal accordingly to ensure you don't fall below it. IE you lift the pedal on inclines, and depress it again on declines.

EBH = Electric Block Heater

ECU = Engine Control Unit (engine computer). Also known as "ECM" (Engine Control Module)

ECT = Engine Coolant Temperature (see also FWT)

EFI = Electronic fuel injection (see also MFI)

EOC = Engine Off Coasting. See also CODFISH.

EV = Electric Vehicle

FC = Fuel Consumption

FCR = Fuel Consumption Rate

FE = Fuel Economy (or Fuel Efficiency)

FWT = Water Temperature (Farenheit) - this is a ScanGauge specific code for coolant temp. (See also ECT)

HAI = Hot Air Intake. See also CAI (Cold Air Intake) and WAI (Warm Air Intake).

HPV = Human Powered Vehicle

IAT = Intake Air Temperature

ICE = Internal Combustion Engine

LHK (or LPK) = Liters per hundred km.

LPK (or LHK) = Litres per 100 KM.

LRR = Low Rolling Resistance (tires)

MFI = Mechanical fuel injection (see also EFI)

MFI = Multiport Fuel Injection. (Single port is TBI, throttle-body injection) See also = SFI or Sequential Fuel Injection. SFI systems operate the fuel injectors sequentially. Regular MFI operates the injectors all at the same time..

MMPG = Man-Miles Per Gallon, number of people in the car x miles per gallon

OBD = On Board Diagnostics - system of sensors & computer(s) in an automobile. Also known by specific versions, eg. OBD-I or OBD-II, OBD2, etc.

OEM = Original Equipment Manufacturer

P&G = Pulse and Gluide. An old driving technique popularized most notably by some drivers of the Toyota Prius (but adaptable to nearly any vehicle). It's a repeated regimen of accelerating to an upper target speed under relatively high engine loads, then coasting down with the engine shut off to a lower target speed. The average speed of a Pulse & Glide pattern is often significantly more fuel efficient than cruising at the same constant speed.

PSL = Posted Speed Limit

ROFC = Rate of Fuel Consumption

RR = Rolling Resistance. See LRR (Low Rolling Resistance).

SFI or Sequential Fuel Injection. SFI systems operate the fuel injectors sequentially. Regular MFI operates the injectors all at the same time.

SG = ScanGauge fuel economy gauge/trip computer for use in 1996 and up North American market vehicles (predominantly). Also "SG1" "SGI" (denoting the first version of the "SG"). "SG2" and "SGII" denote the second version.

SIDI = Spark Ignition Direct Injection

SIE = Spark ignition engine.

SuperMID = Super Multi Information Display. Custom "enthusiast-built" fuel economy/trip computer originally

SVO = Straight Vegetable Oil

TBI = Throttle Body Injection (i.e. single port fuel injection - MFI)

TPS = Throttle Position Sensor

VG = Vortex Generator - aerodynamic device

VSS = Vehicle Speed Sensor (signal used by the vehicle computer for speed/distance functions - eg. for the speedometer/odometer)

WAI = Warm Air Intake

WMO = Waste Motor Oil and Waste Transmission Oil

WOT = Wide Open Throttle. Generally avoided in fuel efficient driving, since it causes a computer controlled engine to enter "open loop" mode, where it burns significantly more fuel than normal.

WTO = Waste Transmission Oil

WVO = Waste Vegetable Oil

YMMV = Your mileage may vary

[betasniper]

Kinda pedantic, but acronyms are pronounceable as words. Most of the list is made up of initialisms (letters pronounced seperately).

Anyway, EOC can on or off and most add letters and possibly parenthesis.
I propose
EFC for Engine ofF Coasting and
ENC for Engine oN Coasting.

[Joggernot]

Pwm ?

[Joggernot]

SAFC = Stand Alone Fuel Control
EFIE = ?

[gone-ot]

Originally Posted by Joggernot

Pwm ?

Pulse-Width Modulation (PWM) ... in electronics.

[RedDevil]

EFIE = Electronic Fuel Injection Enhancer

[19bonestock88]

Originally Posted by Joggernot

SAFC = Stand Alone Fuel Control?

It’s a product sold my ApexI, called Super Air Flow Converter

It’s a piggyback fuel controller