Forums Forums Enthusiast Forums A - Z Autowirral Much difference in types of Petrol

I have been using Tesco's standard petrol, for a while, and have been getting a lot of engine pinking.

Someone told me to try shell V power, I did not think it would make a difference, but how wrong I was, there is no more pinking and knocking, and engine feels a lot smoother.

Shell fuel has extra additives in to help clean the engine ( a mate of mine used to drive for shell), i found this out when I put it in my old zafira, it blew all the crap out, now I have an Astra and always use shell in it.

It does make a difference different companies use different additives whereas a lot of the supermarkets do not keeping their prices down so we get cheaper fuel.

Although after saying this, I use a product called Cataclean every 3 months or so and have found massive improvements on fuel economy, emissions and pull of the engine in my VW Golf 1.9 TDI and the wifes BMW X5. My Dad also uses it in his Mark 2 1986 VW Golf GTI and it reduced the smoking and improved performance!

Shell V Power has a higher Octane rating, meaning it will basically take more compression and heat before it combusts.

In a performance engine this means you can run more timing advance for more power.

On more regular engines there is little benefit from running the higher octane fuel (although they are often a better quality blend) from a performance point of view. If you are experiencing "pinking" from regular 95 RON fuel, Id suggest there is an issue with your car and it is either running lean (this is odd due to your other consumption thread) or it is running excessive advance on the timing.....

Unless a car has specifically been tuned / mapped to run on more than 95 RON fuel, it should have no problems running on regular unleaded. Does the car have a knock sensor? If it has one fitted, this should retard the timing when it detects pinking to help protect the engine.

I started to use shell v power in a rover 1.8turbo and it made a vast difference.
Whenever I use normal supermarket fuel it trips my ECU light because the cat is near the end of its life

A turbo engine uses the turbo to increase combustion pressure, which also generates heat. The higher octane fuel will combust at higher pressure and temps, so will always benefit performance engines, especially those with a turbo fitted. As it burns cooler, your cat wont get as hot, hence the ECU light not coming on when you use it.

V Power and the higher octane fuels shoudl work better with any engine, but any EU car should run fine on normal Unleaded regardless.

when i put tesco diesel in my car (1.4hdi 307), the engine becomes louder and less powerful, hence why shell now get my business unless im really desperate!