OK... i know crap about civic's or there engines. But i do know that with my h22a, if the speed sensor is not working than vtec will not switch over. If vtec does not switch then the ecu will rev limit the car to 6500rpm's(in my s2k its 7000). How ever you might check your timming. Like i said before i dont know crap about civics but i know that all the accords(90-up) and preludes(92-up) have electronic VSS's. so you might have to find a way to splice in the wires or see if the old one will go in to the new tranny. Of course if its manual than scratch what i just said about switching them.