I have checked compression, spark , super charger and pulle belt so on,air supply, changed oil, checked fuel supply, pump is in fresh shape, my 260x is surging quite badly major performance loss. Surge is noticeable worse over 5000rpm, and engine struggles to pull 7000rpm. Oil
Showed contamination seemed like fuel. Assumed I had a fowled plug and was putting raw fuel past rings into oil?changed the set of plugs and flushed oil system replaced filter and oil. Compression cyl 1,4-111psi 3,4-119psi. No alarms or codes showing on dash. I'm not sure what direction to head next with the trouble shooting suggestions welcome