E

E/I

Exhaust-to-intake ratio

E85

Etanol E85

EC

Exhaust closing

ECR

Effective compression ratio

Effective Compression Ratio

The combination of static compression ratio plus boost pressure: boost divided by ambient pressure plus 1 and multiplied by the static compression ratio. It is used to calculate the engine’s compression ratio tolerance for pump gasoline.

Efficiency Island

The irregular shapes of various efficiency levels on a turbocharger compressor map.

EFI

Electronic fuel injection

Engine Cycle Analysis (ECA)

A SuperFlow Technologies Group software analysis program that utilizes a rotary shaft encoder unit on the crankshaft and a pressure transducer in the combustion chamber to directly measure real-time cylinder pressure relative to crank position on a running dyno engine.

Engine Displacement

Size of engine in liters or Cubic Inch Ci. (see CC)

Equivalent Displacement

Equivalent Displacement A calculation that relates the displacement of a rotary engine to that of a reciprocating engine. ED = SV × 3, where SV is the swept volume of one rotary chamber.

Exhaust Closing Point (EC)

Measured in degrees after top dead center (ATDC).

Exhaust Opening Point (EO)

Measured in degrees before bottom dead center (BBDC).

F

Flow Area

Flow Area The available space through which the air/ fuel mixture or exhaust by-products enter and leave the engine’s combustion space. This area is typically restricted at the valve throat area or at some point farther up the port.

FMEP

Friction mean effective pressure ft/ min: feet per minute ft/ sec: feet per second g/ sec: grams per second

FMIC ratio

Front Mounted Intercooler ratio

Foot-pound

Foot-pound A measure of force times distance, or “work.” If you move 10 pounds a distance of 50 feet you have performed 500 ft-lbs of work. If you do it over time, say 30 seconds, you have produced 16.66 ft-lbs/ sec of power (500/ 30 = 16.66). Divide that by 550 (1 hp = 550 ft-lbs/ sec) and you have applied 0.030 hp.

Free-Float

This is a turbo without a Wastegate. Therefore, the turbo is unable to regulate its own boost levels.

Friction Horsepower

Friction Horsepower Friction horsepower is the total power absorbed by the mechanical components of the engine due to frictional forces that oppose motion by converting it to heat.

Friction Mean Effective Pressuren

Friction Mean Effective Pressure This is the loss incurred by friction between the pistons and rings against the cylinder walls and the bearings on the crankshaft and rods. It is a calculated number.

ft-lb

One ft-lb equals 1.35582 Nm and 1 Nm equals 0.737562 ft-lb.

G

g/sec

Grams per second

gal/hr

Gallons per hour

Garrett

Garrett Advanced Motion is one of the big turbo manuffactures, HQ in Rolle, Switzerland

Gauge Pressure

Gauge Pressure-See absolute pressure Intake Closing Point (IC)-Measured in degrees ABDC.

H

Heat Shields

Thin plate that protects & separates the top of the bearing housing from the high temperatures of the exhaust gases. It is positioned between the bearing housing and the revolving turbine wheel.

Hg

Mercury

HP

Horsepower (crank), and Wheel horsepower is usually abbreviated WHP