I can honestly say that wiring the o2 and vtec are about the easiest things you could do with wires on a car. If you know where the ECU is, it's even easier than wiring a stereo
But then I've done some crazy stuff with wiring so my perspective might be a little off.
Yeah, the z1 would be difficult to tune unless you went CA version and didn't run lean-burn at all, but then you're really defeating the purpose.
Anyway, the HF engine with the ZC would probably do well, but if you really ride it hard probably not so much
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