Why does my car overheat in about 5 minutes after startup, and hits a "rev limiter" at about 2000 RPM?....Having just rebuilt my engine with all new internals, the Wiring harness is the stock harness for my 1990 CRX Si, but the engine is a D16Z^ out of a 1994 Civic Si. The previous owner had the care running before and i dont see why it shouldnt now. We removed the engine to rebuild it, put it back in and connected 99% of all wires, especially the bare essentials. I have a brand new P28 ECU, an OBD0 to OBD1 harness it in and a brand new Distributor. Now the car starts easy and idles about 1k RPM but it hits a rev limiter at 2k and it overheats in about 5 minutes. Yet brand new Thermostat and everything. THough before we took the engine out, the few times we ran it it overheated also, so i just dont know. Three Honda enthusiats including myself and my father/broother with 10+ yrs of knowledge cant figure this out. please help asap..