Hi everyone great site ! Now my question ..just bought a 1994 wrx sti (import) and im confused as to what fuel to use.When i bought the car i heard that with imports you've got to use octane booster but, after talking to the guys at Triton Bournemouth(where i bought the car) they said theyve been running them for years on SUL ,without octane booster ,with no problems. Dont get me wrong im not doubting them, but ive read so much on here about engine rebuilds etc, that to be honest im worried!! I would appreciate any comments Cheers Dave

 

Welcome to scoobynet.

The reason why most people put optimax and sometimes booster is the imports from japan are set up from the factory for there fuel which is 100 ron therefore if your using 95 ron this could lead to engine failure.

My opinion for all imports is you get the car re-mapped to suit your fuel requirements and atleast you will know your pride and joy is running ok.

Also you dont know the history behind most of the imports especially if a Joy-rider called tommytookamotor has driven it

R.B

 

If it's standard then it will be programmed to run on the 100 RON fuel they have in Japan as apposed to the normal 95 RON unleaded we have over here.
If its used on 95 RON fuel i wouldn't like to say how long it would last, more than likely it will melt one or more pistons. Unless it's never driven hard enough to bring it on boost that is but even then i wouldn't like to try.

Super Unleaded is 97 RON so using this with a good quality octane booster should be ok as this will normally lift the octane by two points to around 99 RON.
Optimax is 98 RON and is prob regarded as the best pump fuel available in the UK. I've heard of people using this on its own but couldn't tell you if this was ok indefinately. The best you could do with the standard program would be to use this with octane booster which would be more than up to the job but would be very costly to run, think octane booster is about £4 a bottle.

If you intend to keep the car it's prob best to have it re-mapped to suit your chosen fuel as it will work out cheaper in the long run rather than buyin shed loads of octane booster and you'll have peace of mind that the engine is running correctly


Kenny

 

Just to add a little confusion; when this car was made Japan didnt actually have 100 octane fuel..... and this car cant be re-mapped.

Id use Optimax with 1ml per litre of NF Race. Id consider buying a knocklink so that I can see when the cars detonating and I might consider getting a A'Pexi PowerFC fitted and mapped from Andy.F for about £700.....

Simon

 

didn't realise you had replied mate we almost wrote the same thing without knowing!!


Kenny

 

I run my 95 standard WRX on Optimax 98.6 RON plus half a bottle of NF Octane booster per 30 Litres of fuel (maximum dilution). Gives 104-105 RON.

No pinking or Knock. Spectacular throttle response.

Not my everyday car though.

 

Learn somethin new everyday! Wasn't aware that Japan didn't have 100 RON in 94?

When i said get it re-mapped i should have said get an aftermarket ecu as GC8 rightly said, forgot you couldn't re-map the early ecu's ma bad!!

Kenny

 

It was close Kenny; I cant recall what RON exactly hence my not saying (98-99 I think)... Someone like Clarance may know.

Simon

 

Thanks for the replies and advice guys , am i right in thinking that Triton have gave me duff info?