Those with Built Engines or Running in Colder Climates Be Aware!
Firstly I'll note that the overall build quality is great like all GrimmSpeed products. This is not the AOS you want to be running on any built engines. I've tried it on two different EJ builds and it has done more harm than good. This is stated here in red below the product description, but it should be better known. It may be in part due to combining a built engine with colder climate, but this AOS is horrible in cold climates. I'm not much further north than Minnesota, and this AOS design is extremely poor for holding condensation and even dumping it back down the oil fill tube along with the oil that is separated. The issue seems to be with the components not getting hot enough in the colder climates. I've experienced excessive amount of condensation and milk build up, almost plugging off lines and the ports of the AOS itself. For winter I've even blocked off my hood scoop and insulated the lines and the AOS manifold itself with minimal improvements. This product may very well work great on a completely OEM engine. Just be cautious of any other application.