Selling your classic car? It's FREE to list your car on Honest John Classics | No thanks

Would I benefit from higher-grade petrol?

I have driven a BMW E30 318i automatic from new which I had converted to run on unleaded petrol when leaded petrol was phased out. I currently always refuel with Esso Synergy 95 ron petrol. Would a 28 year-old-engine still benefit from upgrading to Esso Synergy Supreme+ at my nearest fuel station or even Shell V-Power Nitro+ unleaded or would the increased petrol costs outweigh the benefits and make such an upgrade uneconomical?

Asked on 4 October 2015 by wegenerp

Answered by Honest John
If you had it 'converted', what they did was retard the ignition to run on lower octane petrol. It will benefit enormously from being advanced to its original setting and from running on 99 Ron petrol and the best is Shell V-Power Nitro Plus, but Esso Synergy Supreme+ is still a lot better than 95.
Similar questions
I have just bought a 1990 Mini Moke, but the dealer is not sure if the cylinder head has the hardened valve seats to use unleaded petrol. Do you think it would be okay to use unleaded? Also, should I use...
I have a 1992 generation 5 Celica Convertible imported from Japan many years ago. I notice that when driving up an incline it seems to 'pink'. I have not heard this before from an injected engine. Which...
I have been trying to decide whether my C-reg Mercedes-Benz 220D, extremely well looked after by a Mercedes specialist family in West Hampstead, would benefit from using Shell V-power diesel. Cost would...
Related models
Image-defining 1980s saloon, lots of options, saloon, coupe, estate and convertible, as well as four- and six-cylinder engines, all well-engineered and good to drive
 

Ask Honest John