After fiddling around with a few different catch can options, I finally settled on the Saikou Michi Evo-specific DC3 dual catch can setup. Its lightweight and very well designed. The Saikou Michi website has a page showing several different mounting locations. Once the cans arrived, I looked at the firewall location and the location below the airbox. There didn't seem to be sufficient room at the location on the firewall, and with the stock battery, it would be necessary to remove the cans to drain them. So I settled on the location below the airbox. The advantages here are the cooler air down there should encourage condensation of vapors in the catch cans, and that location will allow me to drain the catch cans without having to unmount the cans. I will have to jack up the car though. Here are the install pics and some notes.

Here are the catch cans installed. The larger dimensions of the six speed tranny don't leave much room for variability in position. The pinch points are the temperature sensor for the fan, the tranny, and the clutch hardline. Note that one of the hoses for the intake breather can goes behind the plug for the fan temperature sensor. I bent the other nipple so that it pointed a few degrees back, allowing the hose to clear the fan temperature sensor body. I also bent the upper nipple on the other can a bit too. I've talked with Saikou-kun about this, and he is willing to make a "below-the-airbox" dual can configuration with both sets of nipples pointing 30 degrees back. Drilling the Evo frame for the mounting bracked is a bit tricky because of the lack of room to get a drill in there.


I initially tried 3/8" hose coming off the intake pipe, but it wanted to rest on the coolant temp sensor wiring and plug, and I didn't like that. So I used the stock breather hose coming off the intake pipe because it is precontoured to make a tight 180 degree bend. I joined it to 3/8" hose using a 5/16" barbed connector. The 3/8" hose slides loosely on the connector, so a hose clamp is needed.


Here is the routing under the battery tray. I had to route the intake manifold catch can hoses away from the shifter linkage.


Here is the routing of the intake manifold catch can hoses looking down on the engine compartment. I ended up removing the factory PCV valve on the valve cover and using a McMaster-Carr "fast acting" check valve closer to the IM. I didn't like the idea of having to pressurize an additional large volume of air (hoses and catch can). I replaced the PCV valve on the valve cover with a 5/16" barbed fitting from McMaster-Carr. The threads are 1/8" BSPT. I tried 1/8" NPT, but it does not fit. ok to just use the factory PCV valve too.


Just another view of the intake manifold catch can hose routing.

 

Damn with a full size battery & stock UICP you definitely have very limited space! I run a DC3 catch can setup right now too, but with split cans. One mounted on the rear cam angle sensor housing & the other mounted where the stock FPR solenoid would be.

 

Hey! I didn't realize you were with Toxicfab
You guys do some absolutely gorgeous work! and I'm honored you picked my tanks for your project!

Thanks again!

 

I now see what you are talking about.

 

Thanks for putting this up!

I ordered a custom set and am waiting to finish a bunch of other projects before getting mine on. I'll post here or make a new thread (most likely here)

 

Very detailed writeup. Thanks for posting!

 

Here's what I got in the "PCV" catch can after about a month. Based on smell, I think its primarily water. I suspect the can was pretty full, so I'm going to try draining it again in two weeks rather than wait a month. This is why its not good to have a catch can drain back into the crankcase. There was nothing in the intake pipe catch can.

 

Does anybody know if this install location will work with an aftermarket (ETS) U/C pipe on an evo with a 6spd transmission? Thanks in advance.

 

The install location I showed here will not work. Too bad becsuse the cool location worked really well for condensing vapor. Looking for a new location.

 

Oh OK. Rats. Thanks for the info. Maybe back on the firewall on the left side, I was thinking there as a second choice? I'll email Saikou about ordering a catch can. Maybe he can create a bracket to mount to the transmission like STM's square catch can. shrugs.

 

i just got this catch can to mount to a simliar area (somewhere under the air intake) - appreciate the pics! are you using a check valve?

 

^Lol, get a check valve...and responding to your email now

 

lol there's so much more hose used than i thought there'd be.

 

Yeah, its a long run, but the cool air down there seems to be very helpful for condensing out water and oil.

Yes, I used a check valve off the intake manifold. I really like the Boomba check valves. Keep in mind that that the factory PCV valve though as its not just a check valve but also a metering valve, so it has to stay.

 

no i'm the same i can't mount anywhere else anyway. do you have a pick of the check valve?

here's mine btw - i think our spouts are angled differently