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Should I use higher octane fuel?
Good afternoon, I own Opel Astra sedane with petrol 1.4 turbo engine. In users manual, it states that recommended fuel is 95 RON octane unleaded, while 98 , and 91 octane are possible. I would like to know does it mean my car will run best on 95 RON? I know that lower octane is not an option, but will it make any difference if I put higher octane than recommended? I am asking this, because in my country, 98 or 100 RON petrols are higher in quality than 95. Thank you
Our answer:
Hi Todor,
It really depends on how Opel calibrated the engine. In the case of the turbocharged 1.4, we'd expect it to produce a little more power on the higher octane fuel when you extend it. It may also have more torque at low engine speeds, making it feel more responsive.
There's no harm in trying a few tanks of the higher octane fuel to see for yourself if you can detect any difference. Obviously it will be more expensive.
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