Ive actually looked into this before a bit.
Now scaremongering aside, supermarket fuel is rotten, ruins cars etc.
This is more from my understanding and learning from various manufacturers, and personal experience.
High performance engines are developed to run at certain compression ratios. High octane fuel withstands these pressures better. Meaning it can be compressed, and ignited on demand.
Lower octane fuel, doesnt handle the pressure so well. It will do one of 2 things. Either pre ignite, before the spark ignites it. Aka Pinking. This is down to the heat generated by the compression cycle, being hot enough to ignite.
Or it will detonate, a much larger combustion than desired, aka Knocking.
Knock sensors are designed to save engines from damage. They detect knock, and alter the timing to try and compensate. This isnt ideal, its a fail safe really. The car will now be loosing power, due to running non ideal timing and fuelling settings.
A car with a knock sensor can run on lower octane if you must. As long as its not knocking, the ecu is doing its job, it will be down on power, less responsive etc. But if your happy, and the cars not knocking, who cares.
Older cars without knock sensors cant accommodate the change in octane. I set my 205 up to run V Power, and the one time i couldnt get any, i filled up with 95, i cant remember why i didnt get 97? Anyway, it drove like junk, hesitated on acceleration a lot. To the extent, i drained it out! This is because it was still trying to run on 99, and the fuel wasnt up to it.
Momentum, is made by Greenergy, who make a good chunk of uk fuel. They publish up to date test independent test results online.
I know people who swear by it. Including guys who race in PBMW, Compact Cup, M3 etc. I also know people who swear its the devils juice.
Same goes for V Power, some swear by it, others loathe it.
I will run a few tanks of V Power at least, if only for the chemical cleaning properties of the additives they use. That is something i dont think Momentum matches, i think Momentum also has a higher bio content to raise the RON.
But after my few tanks, i will try Momentum. I shop at Tesco, and get fuel rewards, think its 1p a litre per £50 (accumulative) spent. Up to 20p a litre off max i think.
That said, my mileage will be very low now, so cost wont matter as much. So ill go purely off of any difference, if any, i notice.
In summary, run either Momentum, or V Power, avoid anything else unless you have no choice.
Oh, and can we get this moved to the right forum. Be nice for it to see some use haha.
