Cylinder Head - Toyota FJ GSJ10 Technical Manual

3. Cylinder Head

" The cylinder head, which is made of aluminum, contains a pentroof-type combustion chamber. The spark
plug is located in the center of the combustion chamber in order to improve the engine's anti-knocking
performance.
" The intake ports are on the inside and the exhaust ports are on the outside of the left and right banks
respectively.
" Upright intake ports are used to improve the intake efficiency.
" A taper squish combustion chamber is used to improve anti-knocking performance and intake efficiency.
In addition, engine performance and fuel economy are improved.
" Siamese type intake ports are used to reduce the overall surface area of the intake port walls. This prevents
the fuel from adhering to the intake port walls, thus reducing HC exhaust emissions.
View from Back Side
— REFERENCE —
Siamese Type
ENGINE — 1GR-FE ENGINE
A
Spark Plug Hole
A
238EG08
215EG18
Intake
Valve
IN
Exhaust
Valve
Upright Intake Port
Taper Squish
A-A Cross Section
Independent Type
EX
238EG07
215EG19