Performance Car Fuel.

[Von Smallhausen]

As some may know, I have an MR2 turbo and I run it on Shell Optimax, as recommended. It is my understanding that the use of normal unleaded will not cause damage to the engine but you simply lose performance with the lower ron value.

Is there any equivalent to Optimax made by Esso or BP ? Also, I have heard that by adding a small quantity of kerosene to normal unleaded that can increase the ron value to enhance performance. Is there any truth in this ?

Cheeaaz.

 

[Von Smallhausen]

Running a lower RON fuel shouldn't damage your engine if your manufacturer has ok'd this - fuel consumption will probably suffer for using cheaper fuel though. In my manual they state that you can use lower than 97RON fuel if you need to as the engine is protected by a knock sensor.

There was a long thread about this on the BM3W forum a while back, the outcome was basically that it costs the same to run your car on Optimax as on budget fuel, you'll spend less filling up a tank but will see worse fuel consumption as the engine needs more of the cheap stuff to do the same amount of work => So why not just run on the Optimax and safeguard your engine.

I only put Optimax in mine, and I really notice the difference if I put anything else in, including BP Ultimate, strangley enough it doesn't seem to mind Jet though.

Excellent. Thanks for that.

You have an MR2 ?

 

[Von Smallhausen]

I refuse to pay £1/l for optimax/ultimate fuels at the moment. To be honest i will never feel the difference and the money I lose in economy is nothing compared to the extra you pay for these optimum fuels.

I tend to forget such impracticalities when leaving boy racers in a cloud and a wail of laughter !

 

[Von Smallhausen]

As a Japanese import the ECU is mapped for the 100 ron fuel the Japs get. Running 95 ron won't just cause you to 'simply lose peformance', you run a high risk of detonation. Severe Detonation = dead engine.

SUL/Optimax is the least you should run it on. Ideally you should add octane booster (or thinners ) to take it up to the 100 ron it is mapped for.

Seriously ? Add off the shelf paint thinners ?

 

[Von Smallhausen]

Celulose Thinners is basicaly Toluene and Xylene, and will increase octane. It's actually present in many pump fuels in low levels. Be carefull though, it can attack some rubber fuel pipes, and it's generaly not very pleasant stuff to get on your skin too often (though I use it for degreasing all sorts of stuff).

I used to work as an industrial chemist and have worked with both solvents. I just didn't think they could be used as an octane booster.

Toluene and Xylene and both of the Benzene group as i recall and therefore known as potential carcinogens and linked to damage of the nervous system.