For some background, I was inspired to do this dual can setup after seeing this one:
I am not a fan of this spaghetti mess of hoses, nor the size or price of the radium cans, so I wanted to reverse mount some Mishimoto cans using the Fab Factory bracket, but it just wasn't panning out:
And then when I came across this thread and the BMS bracket, it finally clicked for me:
https://bmw.spoolstreet.com/threads/does-the-n54-bms-occ-fit-on-e92-m3-strut-brace.3365/
Now, for the sake of cost and simplicity, I recommend a PCV delete, but swap the filter for a hose and route it under the car or into the intake. However, if you have OCD like me, love AN fittings, braided hose and want to retain PCV function, all while remaining subtly stylish, then you can take a peak below. If you don't want to build it, the VTT catch can setup is the best option out there you can buy, but I'm not sure if their VC is required. This on the other hand will work with an OEM valve cover, and the cans are reverse mounted so more of the plumbing is hidden.
If you are still interested in the way I've done things, the setup consists of:
- 10AN Double O-ringed flapper delete $50
- 10AN female coupler $13.99
- 10AN male union $8.99
- 10AN 90* hose end $8.99
- 10AN 90* to 3/8 NPT hose end $30.22
- 3/8 NPT to 3/4 hose barb $7.40
- Gates 3/4" 90* heater hose $9.19
- 3/8 NPT plug $3.11
- ADE 8AN PCV delete $60
- 8AN female coupler $9.99
- 8AN male union $7.99
- 8AN 90* hose end $8.99
- 8AN 90* to 3/8 NPT hose end $9.99
- 3/8 NPT to 6AN 90* adapter $23.62
- Russell one way check valve $28.59
- 2x 6AN hose ends $8.19
- 1/4 NPT to 6AN adapter $6.99
- 3 port Mishimoto or Mishimoto style catch can $34.99
- 2 port Mishimoto or Mishimoto style catch can $116.25
- 2x strut brace brackets from BMS (wished I bought them off ebay) $40
This does not include the price of the braided hose, the Toyota PCV or the machining cost. I bought a genuine Mishimoto 2 port can, so if you wanted you could save a bit there. If you shopped around on fittings you could probably save some money there too, but this is just what I paid.
If the price hasn't scared you away yet, here is the general guide:
First, start by having the ADE PCV delete machined to accept the Toyota PCV valve. Then insert it into the valve cover, screw on the 8AN female coupler, then the 8AN male union.
Next, take the 10AN flapper delete, add the 10AN female coupler and the 10AN male union. We have to add these extra fittings so it will clear the valve cover. If someone else comes up with a better method, I'm listening but this is just what I did. Go ahead and attach your 10AN and 8AN 90* hose ends and you'll get something starting to look like this:
Next, I used a 3 port catch can mounted with the strut bar bracket, and connected a 10AN 90* to 3/8 NPT hose end coupler to the far inlet port. Then use a 3/8 NPT plug on the near inlet port. If you attempt to connect directly to the near port, you'll find that the fittings bump against the strut bar. If you use the far port, a 90* swivel fitting can be used, which can angle downward and is clear of the strut bar. Now stick the 3/8 NPT to 3/4" hose barb fitting into the middle port, trim and connect the gates hose and stuff the flapper into the other end. I also removed the stone filter from the inside to eliminate the restriction, but I may put it back and leave the flapper off. I still recommend routing the other end of the flapper to the intake pipe or under the car.
Next, I mounted a 2 port catch can to the right of the other one, and inserted the 8AN to 3/8 NPT 90* hose end into the inlet port. Then added the 3/8 NPT to 6AN 90* adapter to the outlet port. Attach the Russel check valve to this adapter with flow pointing toward the manifold. I used a 1/4 NPT to 6AN adapter on the manifold side.
Now measure and cut all your hoses, I used a zip tie and a cutting wheel. You're done. I wasted quite a bit of money in fittings in the process of figuring out exactly what I needed, so hopefully someone finds it useful.
