I'm doing a vitara build on my z6 to replace the stock boosted setup i have. Got a catch can question. If i remove the pcv valve in the intake manifold and the black box on back of the block, can i plug the hole the black box was in and just run two vents off the valve cover to a catch can?

 

yup ( i think it was either a 2$ 32mm or 34mm freeze plug, they made 2 different sizes...or the fancy 25$ plugs), or you can put a plug with fitting in it and use it to drain the catch can back into the engine. B R fittings are reasonably priced and his customer service is great...hes on HT

 

you can but it stinks soo bad from the fumes and really there is no need to remove the PCV valve

 

except for all the oil that will end up in the combustion chambers and drastically reduce the octane of the fuel.

 

yes, just make sure you have a drainback feature to somewhere on the block/pan

i personally got rid of the pcv valve, the black box (bought a plug from b&r fittings) and ran 2 -10 from the valve cover and have a -10an that drains to the oil pan (can act as a vent when under pressure also)

 

I'm in the same bought. I have a greddy style catch can with only two fittings on top. Could I use this for the same thing. Block off the PCV and then run 2 lines to the catch can? With no drain it will probably catch a lot of oil and smell right?

What other options do I have?

 

two -10an fittings off the front of the valve cover minimal, your going to get a little odor no matter what with a catch can setup but this will not fill with oil. ive never had to drain my catchcan once with that setup

 

That only happens if the engine gets super hot as the oil usually clings to the top of the piston. The big problem is the degraded ring seal; building performance motors to not make best power over a $30-150 catch can is shooting yourself in the foot. 95% of turbo Hondas have this problem, a certain percentage of which have catchcans and vents that aren't big enough.

For a given power level, a D-series will need more crankcase ventilation than other Honda motors as it has to make a LOT more combustion pressure in order to push it's smaller piston down just as hard. Also, I prefer block fittings to valve cover vents; compromising oil drainage from the head makes little sense.

 

I've read that catch can thread here but Im still lost.

I want to run 2 lines from the valve cover with an open breather setup. What needs to be plugged in the back of the block? Will this work?

This is a B18B

 

So two 10an vents off the valve cover to the can and a 10an drain back from the bottom of the can to the block where the black box was will be sufficent? Trying to gain some clarity on the best route to take.

 

drain back is not nessesary but you can do it. minimum of two -10an but i always recomend doing 2 -12an's larger line = less siphoning effect of oil. -10 will work though

crankcase pressure is a big enemy and should be delt with like stated above, not spending 501-50 bucks will certainly decrease longevity of the engine from the excessive crankcase pressure. You can even do a vacuum system on the crankcase and actually pick up power but this is not something the average tuner should mess with because if you dont knwo what your doing you can create to much vacuum and actually start to put oil off the surfaces needing lubrication, stick to a breather system and just deal with the oil smell, its not that bad and keep your vents on recirculate LOL

also going to depend on how the motor was built as to how much crankpressure is building, i personally like to run a loose ring gap on my engines which causes a little more pressure and does cause more frequent oil changes but ive had bad experiences with tight ring gaps so thats just my personal preference

 

So If I do what I said all I need is the 32 stop plug?