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hav a 98 jap wrx sti,what is suitable petrol i was talkin 2 a lad he said not 2 use regular petrol is this true?

You can use 95 octane petrol but i would use octane booster added to it,NF or Lucas,bout half a bottle of lucas to full tank,this brings up the rating of the 95.
Or if you can get maxol E5....E5..NOT E85...You can just use that and it should be fine...

Recomended fuel is Maxol E5 which is 99ron car can be remapped to run on standard 95ron usually with octane booster Jap fuel is about 102ron i think and jap spec cars are mapped to run on this there are other options availible i have a built in octane booster in mine i dont know where youd get one or how much it was in the car when i bought it