When I installed my new engine with the afr heads, the car seemed very sluggish, like it was trying to make HP but could not, then after 3 days of driving the car.......boom, it opened up like it was uncorked? I recently had to replace my head gaskets Now the car is running like it did when i first installed the new engine, low power. I am guessing that the engine is adjusting to the mods from stock? It has only been 2 days and no power...yet? Anyone else ever have this problem? I'm sure it will wake up in a day or two.