As the title states. Im about to do this within the next month since i have to replace my clutch but i am curious how many people have done this. I read a lot of talk but no follow ups. What are the benefits if any? I have a perfect working ej20g non closed deck and i got a deal on a ej20h long block. all i have to do is swap over the manifolds(intake/exhaust) and all sensors and this should work right? will my ej20g ecu get retarted even though im running same turbo and injectors? I jsut want your 2 cents. if you think its not worth it or there in no gain please chime in.