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To those of you that use optimax or other high octane petrol, do you notice much difference from the bog standard stuff. Nearest shell garage is about 15 mins away from me. Is it worth the drive?
  Ford Fiesta

try it and see. Ive used it from new so dont know any different. should be aroun 77.9p a litre
  Nissan R35 GT-R

It would be worth it once in a while as it has been PROVEN to clean up carbon deposits on the back of inlet valves etc (see EVO mag).

Higher RON is not a bad thing either as there is less chance of knocking.

The flame is said to travel faster through the mixture, another benifit.

I use Optimax 100% of the time and shall continue to use it. I have not had, or heard of any problems with it.

1 happy customer

i use it all the time you can really notice the difference the car runs a lot smoother. Try a tank of the normal stuff then use a tank of optimax and see if you can notice the difference......... its not even that much more expensive.

Definitely notice the difference (although its probably just in my head!). Seems to be a lot smoother and the throttle pick up more instant.....
  Mk4 MX-5, Smart 451

i use it 99.9% of the time (unless i get caught out with no petrol miles away from a shell garage), and there is definately a difference, the car seems to accelerate and drive a lot smoother, and for the extra difference in price it is pointless settling for the normal unleaded.


Dunno if it is a coincidence but I tried a tank of Optimax a month back. Up until then I hadnt any problems starting but after filling with Optimax, the starting-up was very unreliable. I reverted back to 95RON and the starting up was ok again.

I dont know if its down to dodgy ignition timing, bad tank of fuel or just coincidence.

I intend to try another tank at some point, to see if the problem recurrs.
  172 Cup, V6 255, Williams

Comparing my latest MOT results to the ones I have before I bought the car seem to suggest that somthings changed. The bloke before me used to use normal unleaded, I use optimax. The emissions test figures from my last MOT were nigh on perfect. Only difference...fuel.

The MOT bloke commented on the car and its figs and he seem sceptical that optimax would have anything to do with it, but Im not so sure. I think it probably has, and I am very very sceptical about things like this. So IMO optimax is beneficial (christ did I just say that!)


I notice no difference at all.

and personally think its just a load of BS advertising blurb..

If it is known to clean carbon deposits off the back of inlet valves then would be worried lol.. carbon on the back of inlets is a sign of a knackered unit...

did you mean exhaust valves ??

  Nissan R35 GT-R

Sorry capt. you are quite right.

The inlet valve deposits are not carbon at all, they are tar-like (layer upon layer of unburnt fuel I suppose), but the result is that Optimax did in-fact clean it.

If anyone is interested, a very good test was conducted in EVO issue 044. I normally take notice of what these boys have to say more than anyone else.

Cheers - Laurence.
  Scirocco GT TSi DSG

Cooper S boy

Congrats on your new car, plus excellent choise of colours.

I, like you have to travel about 15 mins to local Shell garage that is owned by BMW in my case, so see lots of Cooper S Minis. I live 1 mile from the largest Tescos in Europe but I have always used Optimax as it gives me an excuse to go for a drive. As for extra performance, I dont know, probably not much, but if it does treat the engin better than regular petrol then I will continue to use it.

as far as the additives etc. in it i dont know. what i do know is that its almost pointless using a higher RON fuel if your timing isnt set to match. unless you can advance the ignition to make full use of it then all your doing is making it less likely to pink (which i doubt clios would do on 95RON anyway) i used to use optimax on my Escort, and with the timing set right it was definately more responsive and a LOT quicker. the main problem however was 1) the price 2) if your in the middle of nowhere without a BP or a Shell garage and NEED petrol... youre screwed, coz beleive me you WILL pink on 95RON
  CTR EK9 turbo

I only fill with 98+ octane as it says to do so on my filler cap door! "98 Recommendo" or something! It idles like a boat on 95 octane boat fuel but seemed to be better mpg on 95 octane? possibly because i didnt want to thrash it. Its magical stuff that optimax..... its like pouring liquid gold into the car when you fill up.
  Skoda Fabia vRS

my car changes its mind all the time, i used Optimax 99% of the time and always thought it was better than the normal stuff, now my car seems to like the normal stuff more

my car cant adapt to the RON so i guess the difference is in my head or due to other things