figone007

I was wondering if anyone could help me with this one. I'm working on my bro's car and I just dropped a USDM OBD2a b18c1 into his EG (I should have gone with the JDM one I know, but it's done). Anyway, he had a JDM D15 with a P13 ECU and it was wired for Vtec. When I dropped in the B18 and tried connecting the USDM P72 (using an OBD1 to OBD2 converter) everything works fine but there is no Vtec. Am I right in thinking that if the harness was rewired for Vtec on the P13 it should work on the P72? Can anyone help? Thanks.