99 or 97 RON petrol in my tank. I'm now running electronic ignition. Would I break my van if I ran higher octane fuel?
Nothing at all will happen apart from you being poorer. It is possible to tune your engine to run better on it but then it'll run worse on 95 RON. Some engines do naturally run better on it, Ted for example.
The only beneficiary will be the Chancellor of the Exchequer. The local Shell garage has been running a hard sell campaign for the 99RON seemingly regardless of the vehicle at the pump.
If it's a crappy knackered old engine it's a waste of money. If it's got a higher compression ratio to stock it will run like it's on rocket fuel
Unless you've been shaving your cylinder heads recently, it'll make b*gger all difference. Your engine will actually run on wildebeest urine (although not very well).
The only benefit might be that apparently there's no ethanol in super unleaded, so you might avoid the associated problems.(see 'petrol' threads ad infinitum)
Try Methanol. Now that's proper fuel, you can't even see it burning, you only know it's on fire when you get decidedly "warm".
My dad said he used to run his vincent blackshsadow on Methanol when he worked in the ICI labs. I reckon he stole it to be honest but he said it used to run great. One of my mates used to run his car on avgas which was 120 octane until he was caught and done for fuel excise duty.