spark ignition engine specifications

A single-cylinder high-compression-ratio engine with the specifications was shown in Table 1. The tested engine was designed so as to enhance thermal efficiency under lean conditions around an excess air ratio λ = 2.0. The in-cylinder tumble flow was enhanced with a long stroke and a customized intake adapter. The fuel used in this study was a high-octane gasoline. The port fuel injection method was used for fueling.

Table 1. Engine specifications.

Displaced volume563.3 cc
Stroke127.5 mm
Bore75.0 mm
Connecting rod242.5 mm
Compression ratio15:1
Number of valves4
Exhaust valve open (at 0.1 mm lift)68 deg. BBDC
Exhaust valve close (at 0.1 mm lift)24 deg. ATDC
Intake valve open (at 0.1 mm lift)22 deg. BTDC
Intake valve close (at 0.1 mm lift)78 deg. ABDC