Performance Car Fuel.

Von Smallhausen

Von Smallhausen

Von Smallhausen

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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. :)
 
BP have their derivative called BP Ultimate think the RON value is the same as optimax i haven't heard of the kerosene idea but i know some people use Octane Booster you can buy in performance cars.

thedazman
 
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.
 
Garrett said:
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.
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Excellent. Thanks for that. :)

You have an MR2 ?
 
BP Ultimate = 97RON
Shell Optimax = 98RON
Esso Super Unleaded = 98RON
Tesco Super Unleaded = 99RON

Optimax is supposed to be the "cleanest" out of them all, that is, it has better/more additives.
 
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've always been lead to believe and understand that higher RON fuels make more of a difference on forced induction cars than standard petrol cars. Didn't 5th gear or Evo mag to a test on this and worked out that it was negligible until you throw a turbo in the works?
 
If your car is a Jap import then it would depend on what sort of fuel remap it has had , normally it would be remapped for 98 RON , 95 RON petrol could well do damage in the long term
 
You might thnk Penski is joking, standard thinners are 114 Octane and run like petrol in a petrol engine. I have run my Vespa on it and it's completely happy.

Add 10% to your cheapo petrol and you will be knocking on 100 Octane and in those quantities it is considered a fuel additive by Customs and Excise so legal as you like too.

At £13 for 25 litres it's cheap too.
 
Von Smallhausen said:
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.
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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.
 
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Rotty said:
If your car is a Jap import then it would depend on what sort of fuel remap it has had , normally it would be remapped for 98 RON , 95 RON petrol could well do damage in the long term
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Mr2 turbos were originally mapped for 100 RON.
 
lukechad said:
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.
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I tend to forget such impracticalities when leaving boy racers in a cloud and a wail of laughter ! :D
 
Adding kerosene will not increase RON as it is a measure of octane purity, so adding it will lower it. I would not think it is a good idea either, it is more carbon dense than Diesel and you wouldn't put that in your tank would you? :p
 
Von Smallhausen said:
I tend to forget such impracticalities when leaving boy racers in a cloud and a wail of laughter ! :D
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Heh, I leave everyone in a cloud of laughter no matter that fuel I use ;)
 
On a turbo engine on standard boost and its been remaped for UK fuel, you might be ok to run on normal unleaded. Personally I put the highest RON fuel in because turbo engines can be susceptable to detonation if tinkered with and I want the added protection just in case.
 
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