Please can somegive a definate answer on fuel as I am confused???
Sorry if this has been done before but i keep getting different advise...

I had a Uk spec 2000 "X" reg from new and ran it on normal unleaded, I was told by the dealer to treat it super every 5 or 6 tanks, - I didnt notice any performance or ecconomy differences.

I have just got a 1999 "V" WRX Jap import and ran it on super, then on just unleaded - I have now been told this could be why the engine melted :( :( :( :( :(

Can this be true????

You should use Optimax along with Octane Booster.

With my UK MY02 WRX the dealer told me it was fine to run on regular unleaded, but performance would be better if I used Super or Optimax.

So I do if I can, but I don't worry about using regular unleaded when it happens.

opinions differ on UK cars - some people (including Subaru UK and Prodrive) say it is fine to run normal unleaded. Many disagree.
However, as far as I am aware, you must NOT run a Jap import on normal unleaded as it is designed to run on much higher octane fuel. This could well be why you melted the engine
I think you should run SUL/Optimax and an octane booster.
I am no expert and don't run a jap import but in the absence of other replies I think you should run on SUL as the absolute minimum.

Steve

I've got a UK MY98 Turbo, in my flap (oh er missus) its says to run Super Unleaded, since owning it Nov 2002, I've used BP SUL and Sainsbury SUL but more recently I've used Optimax, I've occasionally run it on 95 when I've been stuck in the middle of no where and not a shell station for miles. From my experience my Scooby runs a little sweeter on Optimax.

Import wise, from my understanding I thought you had to run Optimax with Octane Booster, as in Japan they run 100 RON fuel.


Cheers

Dan

Deffinetly Optimax and deffinetley an octaine booster.

Without a remap you need to simulate the Japanese fuel.
This is 100-102 RON

unleaded = 95
super = 97
optimax = 98
optimax with booster = 100

NF booster is proven to be the best, however many people on this board will also swear by millers.
Millers is much cheaper than NF, so you take your pick.

Hope that helps to stop you blowing it up again.

Alternatively, speak to Bob Rawle or John Banks about getting a remap. This will allow you to run optimax only and make your engine much more suited to our fuel.

I have found the better the fuel the better they go, well mine does anyway. Hates unleaded goes like a cold diesel van, quite likes sul loves optimax!!!!!!Use to run super and pro boost in my B4RSK but that was a import.That also obeyed the above run so pay your money take your chance

AFAIK all UK spec. cars MUST be able to run on normal
unleaded as part of government legislation. But run better
on higher octane.

Imports are a different story, as they run on 100+ RON
in Japan so I couldn't really comemnt on that.

I've got a MY 94 STI and run it on straight Optimax. Never get any bad indications on the Knock Link. I have seen people say on this net that their cars seem to run most smoothly on Esso SUL but get the best anti knock protection on Optimax. Certainly would not consider 95 RON petrol.

Les :)

My99 uk spec.

1st tankfull of ul was ok
2nd was sul...better
3rd optimax...bit better
4th back to ul...total sh*te in comparison
now either sul or optimax if i can find it.

worst petrol i've ever used was jet.