Last year I tuned a B18c ek9 with S2P2's... made just 120whp peak. Told the owner he didnt have enough compression and the S2 valvesprings were also sapping power. He booked in again and a month later returned with Type-R cams and valvetrain which made 156whp SAE. A great contract but shows you realy need that compression for the S2P2s. Hope that helps