Originally Posted by SRT6 Gang Member
Those running 100-oc fuel, usually have a “hot” tune to compensate. States side, the highest oc pump gas I’ve seen was 94-oc and no one has encountered your situation with pulley/ intake mods on it. I would have to assume that the 98-oc in combination with your pulley and intake is cause for a tune.
Their way to calculate octane (RON) is different from what's used in the U.S. (AKI). 98 octane there equates to ~91 octane by the way we measure it here in the states.