delgado900 said:
Does the oil catch tank need to be fitted at the same height as the rocker cover ? What effect would this have on the performance of the engine ? How regular would the catcher tank need to be emptied ?
you'll want it lower than the rocker so it runs down into the tank, there wouldn't be any performance gains apart from if your engine does throw oil it'll stop your nice shiney throttle body getting covered in the stuff, my engine doesn't put any down the breather so mines clean as the day i put my breather hose on but on the other hand my wifes 2.2 astra cab puts a small amount down but not enough for me to worry about catch tanks.
empting it would all depend on the amount that goes in and how big the tank is that you fit.