Em1250

I got a Honda civic si 2000 with a b16a Japanese version engine with p2t ecu but my vtec harness was cut and I'm looking for a new wiring harness but I don't know what kind harness I need to get for a b16a

1999 Civic Si

Are you looking for just the vtec portion of harness or an entire engine harness? If it is the whole engine harness it has to come from a 99-00 civic Si (USDM, I am not sure on the Canadian market) or a manual transmission 99-00 civic EX (I believe) and you will have to extend the vtec plugs & I think the distributor plug is different as well. As far as I am aware those are the only plug & play oem harnesses (one of them still requires modification of course). You can get aftermarket harnesses as well, just depends on how deep your pockets are.

Em1250

how much would it be for aftermarket? And where can i get one?

1999 Civic Si

It depends on who you go through and which harness you get. A couple companies you can look into are Rywire & wireworx, I currently am drawing a blank on other companies that offer engine harnesses. lol