BME Product Update: Street Catch Can

I wanted get an update out about one of the products that BME will be producing. Although it is taking a long time to get things moving, we are still working hard to get our own products out to the market. Our priority has currently shifted to meeting a mid-September deadline on the STI, so that has become the focus for the time being. Additionally, we refuse to release anything that has not been tested thoroughly.  The good news with this though, is that completion of the STI means a LOT of the BME prototypes can be tested since the reason for designing these parts in the first place was because there was not currently an acceptable solution for us on the market. The new product R&D cycle for something that we are designing will not be inherently fast unlike how it is for some companies who just like to throw something out to market as soon as possible without regard to quality or functionality. It is also not a cheap process so we only ask that you bear with us as we get rolling and keep in mind that anything we deem ready for release will be worth the wait time and it will show in the quality and function of the product. I would also like to point out that with every product we release, we want to have full or nearly-full disclosure of the design process and methodology behind why we design the product the way that it is. That is something you will notice with this post. So without any more rambling, here is the product update.

First up is the “street” version of our catch can. This can is an atmospheric venting can, the reason for this design is that it makes it physically impossible to ingest blow by oil into the intake tract of the car. The crank case and heads are pressurized above atmospheric pressure, by venting to atmosphere, the pressure differential allows the gasses to flow out of the vent ports where they are filtered by the can and released. On a lower power car, specifically one with a stock engine, it is not necessary to put the can under vacuum to help extract vapors. The can features an internal baffle and mesh system that provides thousands of surfaces for the blow by oil to touch and condense on before the air is finally filtered and released. Additionally this is a catch can breather tank, meaning that it does not recirculate the condensed fluids back to the engine. The reason for this is that most of the fluid in the catch can is not oil, it is condensed water vapor. Unless you have serious problems or have over filled your engine to the point where liquid oil is spilling out of the heads, then the amount of actual suspended oil in the air coming out of the breathers is minimal. You don’t want a bunch of condensed water and sludge flowing back into the engine and for that reason we left the tank with a manual drain that, typically for most people, will not need to be drained more frequently than your oil changes. Finally, the tank features large ports to allow for maximum flow of the vapors. Most tanks on the market for the WRX and STI from the “reputable” manufacturers have small half inch ports. The problem with this is that the breather on the crank case is 3/4” and the two head breathers are each 1/2”. Combining two 1/2” lines into another 1/2” line and reducing a 3/4” line to a 1/2” restricts flow, our tank features large 5/8” and 3/4” inlets to allow as much blow by gasses to flow into the tank as possible.

We will be recommending the “street” catch can for people whose cars are more of a daily driver, stock engine and lower power car. They may see some track days but are certainly not any kind of an extreme build.

Our prototype can was installed on a customer’s car on Wednesday. This customer will be testing the can for an extended period of time for us and will provide some data on how well the can functions. His kit is by no means production quality but the can itself is the exact one that will be in the kits. As part of his testing he is running in an HPDE this weekend at Mid OH so this can will be getting a thorough test. The picture below is kind of rough, it was taken with a cell phone but this was test fitting the can on our STI. I will post more updates and pictures when he returns from his track day this weekend.

We do have a “track” version that will use a vacuum and will be much more complex, this is the version that we will be testing on the STI. Also, on a track car where over filling is a common practice then you would want a recirculation can and that will come into play on our “track” can as well. Once we get the prototype for that done, I will be updating people on that version which will be much different than anything on the market right now.

Thanks for checking in, hopefully people like seeing what goes into the R&D process. Check back next week when I get the data on this can from the track weekend.