The RX7 has a PCV that vents through the intake (not certain but I believe that's how it works). It vent's from a largish vac line looking port on the oil filler neck (again, not certain, would appreciate being corrected). It's said that during a complete emmisions remove process the PCV can not be blocked off permanently because it will allow pressure to build in the crankcase and cause general mayhem and havoc. This is solved by a catchcan that attaches to the PCV line, has a filter on top, and then has a dump line. OK. Now, why couldn't you cap the PCV port and then modify the oil filler cap to allow a small filter to be placed on top of it?

 

i think i know what your talking about, and i was told you can just unplug that larger hose off the oil filler neck. just take the hose off and let it vent into the air...unless you care about pollution

 

but that sprays excess oil everywhere.

 

why not just do a catch can? It is not that hard to do and it keeps the engine clean. What you are venting are mostly fumes, with a little liquid too.

 

it's a scale...on one side there's "free" and on the other side there's "costs some money". Some times one side is heavier than the other.

 

My catch can cost me about 15 dollars to make. It is not that big of a cost unless you want some badass chrome ****.

 

not sure if its the best idea, but some people block that hose off and drill a hole on the top of the oil cap. the people ive seen do it, ive seen their cars and never saw oil sprayed everywhere. in reality, oil doesnt spray upawrd that high anyway. remember, theres no pressure in the oil pan. pressure only builds once its sucked up by the pump. start the car and take out the drain plug and youll see. the oil doesnt shoot out any faster with or without the engine running. so im not sure really how much oil will even spray out of the hose on the filler neck by just disconnecting it

 

In old fashioned cars they used to run a line down to the ground. The only thing that the PCV is really used for is to recycle hydrocarbons(thats why it runs back to the engine) and to ventilate the crank case. If you have to get e checked and can get away with running this to the ground and not get noticed you might be better off.

 

ok--it won't spray much oil around, but you hafta think about the fact that someone went and came up with the catch can for a reason, right?? This was most definitely from experience guys. I think it's cool that you are trying to be innovative in your thinking, but some things are just too simple and cheap to improve upon, and honestly I think this is one of them....You would save a few bucks if you just ran a line down or if you run a line out the oil cap, but you will hafta clean the engine bay more often, so there goes your savings....if you run a line down, and you hafta go thru inspection, you could get into a bind there anyway.....