you're not sure im trolling because im suggesting if you open a huge port to atmospheric on your IM, behind your TB, you will idle at a very high RPM?

 

Well I mean, the pcv is kind of already fully open when the manifold is under vac and closes as the manifold pressure becomes greater than the pressure in the cylinder head.

 

Not true. It's fully open the closer to atmospheric, with more vacuum the plunger reduces the flow as it's sucked up against the inlet. it only closes completely with boost.

 

I'm a little offended that you think i'd be stupid enough to not plug that hole. IF i do this, it will not be the first time i've removed a PCV system entirely. But previously that was on motors ingesting well more than 20psi of boost. (WAY overfilled, you know?) Or on a motor that no longer had an intake manifold.

My simple question was whether or not that'd be stupid on a BP that won't see more than 18psi at the most. If i want to go over that, it'll be on a built motor and i'll re-visit the subject at that point.

 

I think he means capping it off lol.


What about the MSM PCV?

 

I have an MSM with an upgraded turbo that's about to get tuned @ 15psi or 250wtq, whichever comes first.

Hence the questions.

Is the MSM super awesome or something? I know on other motors we used to snag the 323GTX PCVs because they held up better under boost in theory.

 

most people here will plug that hole and weld a second bung on the other side where it has better baffles.

 

Excellent, then just run both vents at that point to a catch and call it a day.

So that answers that question, but is this something that would be overkill and more work than it's worth to do on a "mid-boost" MSM? (I'm not sure if that qualifies as over-filling.)

 

I'd just let the factory catch-can do its job.

 

Yeah I dunno just figured it's an OEM valve designed to take boost and easier to source than the 323GTX valve.

 

Cool, thank you.

There's some issues with the factory catch can and how terrible it is, but for my street car, not likely to be a problem.

 

i mean, the same can be said for the MSM turbo setup and ECU alone... so.

 

I don't know what you're talking about. Clearly it was the turbo Miata Mazda should have created.