Me Blog!

Grandad is giving running a series on how to drive here in Ireland over on his blog. But what if you don’t have a car yet or planning to change the one you have? There is one simple thing that people when looking for a new or used car tend to forget. In fact it is probably most likely that they never knew about it.

Petrol.

Yep, petrol or gasoline if you are from the other side of the pond. This subject popped up again in the pub last night in thanks partly to myself. I was moaning that I have to go to Dungarvan (14 miles away) or Midleton (17 miles away) to get petrol and I was met with a few blank stares. Followed by more than a few questions.

Here in Youghal there are four petrol stations. Most popular would be the Amber station as it’s the cheapest. There is a former Texaco which is now called “Great Gas”, a former Esso now called “Vivo” and another former Esso which although still branded Esso is now selling TOP fuel. That’s why their fuel is typically cheaper than global brands. It’s all to do with the additives see?

What they all have in common is that the petrol they sell is rated 90 octane*. In a nutshell octane is how explosive a petrol is. The higher the number means that it ignites less readily than a lower rated fuel. Why this is important is that a car that requires a high octane which has been filled with a low octane rated fuel can suffer from pre-ignition. That is the petrol/air mix can actually explode before it has a chance to be ignited by the spark plug. A sign of this is a pinging or knocking sound coming from the engine. You may also find that your average fuel consumption decreases if you are using a low octane rated fuel where you should be using a higher one. The reverse of this can be true as well.

The recommended petrol for my Saab is 95 octane. The absolute minimum recommended is 91 octane. Typically turbocharged cars require a higher octane fuel as these engines tend to run under higher pressures and therefore run hotter than a normally aspirated engine. This is where pre-ignition can do some serious damage to your engine.

Incidentially you might have heard about bio-ethanol as a fuel source? The octane rating for that is usually over 100. Cars like the new bio-power Saabs can run on both petrol and E85 however as the engine tuning is optimised for either it will get less mileage than a car tuned specificially for one or the other.

So if you are planning to buy a car be sure to check the fuel it uses before you buy. You could be like me and wondering why great big clouds of white smoke appear for a couple of minutes after starting the engine for the first time each day. As well as that overtaking and just accelerating tended to be sluggish. Since changing to just using 95 octane fuel I’m getting much better fuel consumption and the engine is running much smoother too.

So where to get 95 octane rated unleaded petrol? Normal Shell V-Power is 95 octane. As too is normal Statoil, Esso and Texaco unleaded. Generally the global brands will sell 95 octane.

If you have a Japanese import you will probably have to use the more expensive “Premium” brands as typically the most widely available fuels over there is 100 octane. This doesn’t apply to Japanese manufactured cars specificially produced for the European market.

There you go. Now you know

* For anyone in the Americas or Canada reading this the octane ratings that I am referring to are RON ratings. Ye use a different rating over there called MON or more commonly an average between the two called the AKI.