Hi everyone,
I live in a very hot country, average 30+ degrees Celsius...so what type/ brand of engine oil would be the most suitable for my 2002 Legnum VR4?

Unfortunately we have very poor fuel quality, but I have no idea what grade of gasoline it is...but maybe worse than 95 in UK?
I understand the VR4s are programmed to take good high octane fuels( like the fuel in Japan)...so what can I do to solve this issue?

Thank you.