rb25 problem

[240sxwanted]

Ok ive noticed that when my rb25 is not warmed up all the way, it pulls nicely and doesn't bog or lag as mush as when the engine is warmed up. When its semi cold i can get on the gas and it wont bog and lag. When the temperature needle is at the halfway point, i hit full throttle and it seems to pull not as hard as when its not fully warmed up. It also bogs a little. Its pretty much a stock rb25 except for isis intake manifold, fmic, rb25 turbo w/rb20 actuator (10 psi). I also have the stock skyline radiator and some rubber hoses, and has the original spark plugs that came with the engine, if that info helps determine the problem. Anyone else with an rb25 has experienced this?