Spark Plug for 4AGE BT 20v engine is IK20.
For further information, u may refer this website
http://www.globaldenso.com/en/products/aftermarket/plug/basic_knowledge/heatrange/index.html
Want to ask about the GTT normal oil pressure?
1) when the car idle, it is below 4 or above 4?
2) when normal driving, it is below 4 or above 4?
3) when high rpm, it is above 4 or below 4?