A2Speed HEMI Valve Cover With Self Draining Air Oil Seperator
A2Speed is proud to announce the first in a long line of innovative products. Our valve cover incorporates a self draining air oil separator. No more keeping up with the inconvenience of dumping your catch can. Our valve cover fits all GEN III HEMI motors, including the Thitek aftermarket heads. It even keeps the stock O-Rings!
- The system has an optional integrated air-oil separator. The Air Oil Separator mounts to the valve cover where it drains directly back into your Hemi Engine. The Air Oil Separator utilizes a built in check valve to ensure that no raw crankcase atmosphere is drawn from the valve covers to your intake manifold. The internal filter utilizes a special Phenolic material only found in our air oil separators to handle the extreme thermal requirements represented by an engines oil.
- The cover is clearanced for high lift cams, and has about 120 thousands room for milling additional clearance if required.
- The cross sectional thickness of the lower “half pipe” is designed to allow for an AN fitting to be installed, above the rockers, for oil return applications. Great for turbos, as an example.
One commonly asked question we hear alot; Is it bad to drain oil from the catch can back into my crankcase?
So this is a common miss-conception; that a "catch can" is intended to clean the oil. It's function is an air / oil separator (AOS) for the PCV (Positive Crankcase Ventilation) system. Since the 1960s the EPA has mandated that blow-by gasses from the crankcase not be vented to atmosphere. The solution was the PCV system, where the blow-by is diverted to the intake and ingested by the engine. One of the problems with this system is that along with the blow-by gasses you have particulate oil mass (liquid oil droplets). This is bad because oil has a very low octane value, which can reduce the effective octane rating of the fuel in the combustion chamber. Oil also burns dirty and has a negative effect on emissions systems. The answer to this problem is installing an air / oil separator somewhere between were you draw the blow-by out of the engine and where it enters the intake air stream. EVERY engine that has a PCV system has a AOS of some type. In the early days this might have been a simple fiber mesh that sheared off the oil droplets and allowed them to drain into the bottom of the air filer housing, to be wiped up when you changed your air filter. Modern AOS systems are more sophisticated and effective; and share a common feature…once the liquid oil mass is separated from the blow-by gasses, it drains back into the crankcase.
As a side note, if you put a supercharger on your GEN III HEMI that replaced your intake manifold, you just removed the stock Air Oil Separator. (On a 6.4 It’s the square box built onto the side of the intake manifold that the PCV valve fits in. You should consider doubling up on your aftermarket “catch cans”; remember how much oil it caught even when the engine had one built in?)