Hey guys how's it going, I got a 1989 hatch with a b18a1 & a si head I believe . I bought the car as my first car & I'm pretty new to the honda game so I was just wondering what I would need to do this b20vtec swap . It has an obd0 ecu, but the vtec engages so I was wondering if I could just drop the b20 in there as is or if there would need to be some conversions done . I have no clue what the previous owners did to it . So please any help would be greatly appreciated .

 

Pictures. Start with pictures. One of the whole engine bay. Try and get the head code in a shot if you can. Get the block code. Get the ECU code.

I'm not sure what a Si head is? If there is a B18A1 block with the GSR (B18C line) head? Or is it a B16A head? It has VTEC? You said it engages. That leads me to believe there is either a pressure switch/RPM switch thing going on or a weird ECU in use.

Start with pictures. Definitely get some good pictures. The B20VTEC swap is easy and straight forward in my opinion. Mating the head and block is the hardest part as far as I am concerned. The rest is standard swap stuff.

 

B16 and ITR heads: PR3
GS-R head: P72

 

Okay then il try & get some pictures up for you guys as soon as I can since I'm about 3 hours away might be a few days. I have a a few but I'm not sure if they'd be of any help . I believe it's stamped pr3-3 99 on the head it's a b16 head from what I've heard from my buddies . & yeah the vtec kicks in but I think my ecu is a chipped obd0 but only going off of what my friends have told me .