More normally a hybrid conversion with the RB30E block in addition to a twin cam RB25 head with out a turbo is also used being a basis to the RB30DE.The RB25DE cylinder head from the A31 Cefiro C33 Laurel or R32 Skyline (aka: Non VCT) could be used. The RB25DET (with the R33 Skyline or C34 Laurel or Stagea) head is additionally used, having said th