I have read the posts on the merits of Shell V-power 99 ron fuels, could someone tell me if using these fuels could in the long term burn out the valves, in my handbook Octavia turbo 4x4 it states use fuels 95-97 ron, and only this standard, I only use BP ultimate 97 ron, seems to give a better mpg.

I'm using Shell V-Power in my (tuned) 4X4 having previously used BP Ultimate. The handbook says:

Fuels with a higher octane number than specified can be used without restrictions. This does not offer any advantages in respect of engine output and fuel consumption, however!

The Octy vRS is meant to be run on 98 RON. It will run OK on 95 RON, but will produce less power.

I run my (tuned) one on Tesco 99 RON.

This may well be a silly question, but I'll ask anyway. Diesel, how is that rated and is there any one better than the others.

I've a Fub VRS and it is the first diesel car I've had, so don't know how it works on um.

I ran my old car on V Power, and with a remap to run it there is an advantage over 95 ron. I would say you do get better MPG. I've never seen anything about it burning anything out though.

from memory diesel have a system of "how well they burn" rating, think its a cetaine rating.

Edit;

Here we go BP Ultimate UK - Higher cetane

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