rb25DET PROBLEM PLEASE HELP

[tokyowheels4real]

So I bought a s14 with a rb25det series one, the head gasket blew and it probably demge more because it got extremly over heated, the fan didnt turn on.. So i replaced the head gasket but it wouldn't fire up... So I bought a whole new MOTOR , RB25det NEO 6, swapped it in, turns on but the gas throttle is not reponsive and it lags very much, What could be the problem? do i need to swap anything else ecu, cam, coil pack?

[dbeiler]

NEVER attempt to fix something by simply replacing a bunch of parts. It will be a huge waste of time and money, not to mention, a very sour learning experience. If you do not feel competent troubleshooting this, find somebody else who is. Start with the basics: check engine light, compression test, vacuum leaks, etc.

[dbeiler]

Are you asking if the NEO ECU, coils, etc must be swapped in along with the RB25 NEO block? Yes they must, because the NEO uses smaller injectors than the RB25 S1.