1976 280Z Restoration Project

[wheee!]

Tapped...

I might powder coat this one rather than polish...

[Zed Head]

You'll suck unmetered air (doesn't go through the AFM) in to the intake manifold.  Through the catch can, then the valve cover, crankcase, PCV hose, PCV valve.  Big no-no if you plan to keep the EFI.  Plus you've lost the baffle that stopped oil spray.  At lower RPM you'll run lean (may not even run), at full throttle you'll blow oil vapor in to your catch can.  Looks great, just not as functional.  A well-tuned 280Z won't run with the filler cap removed because of the air leak.

Carry on though.  You'll come up with something that works, I'm sure.

[wheee!]

I was thinking of my latter suggestion as the way to go.... Valve cover and pcv to catch can then catch can to check valve in intake. No loss of vacuum and no unmetered air!

[wheee!]

And the baffle is still in place and functional....

[Zed Head]

You'll have a sealed system but little air flow.  No fresh air supply.  No purging of the crankcase.  The PCV system is more sophisticated than it looks, it has fresh air flow through the crankcase, carrying moisture vapor and other combustion byproducts out.

Don't want to muddy up your thread, just hate to see a lot of work going to something that won't do what you thought it was going to do.  I would just run a section of hose from your new vent position to the same spot the old one was.  Put the can in between if you still feel the need.  Might keep the intake cleaner.

I'll stop now.

[wheee!]

Now I'm confused. I'm doing exactly that... No new air introduced, all lines going to the intake as per factory, just going through the catch can instead of direct. Valve cover plug is still under the baffle... Catch can vents directly to the pcv check valve under the intake. Stock plus catch can! Am I missing something?

[wheee!]

Intake:

The pcv check valve is under the centre section.

[wheee!]

Brake booster and vacuum lines:

The pcv is just to the left of the brake booster connection. Out of frame.

[Zed Head]

All four hoses to the can removes the "positive" pressure differential that causes the crankcase gases to be purged.  Air could flow directly through the can to the PCV valve without going through the crankcase.  The crankcase would be dead air.  The ports are separated and placed to cause the "positive" part of PCV. 

The PCV system has some fine details.  Looking at the diagram you can see that a stuck open PCV valve can also cause a leak past the throttle body.  Could cause a high idle problem.  I'll have to remember that one.  I've wondered also why there are so many different PCV valves, all with the same threads and from factor.  There must be some fine tuning of the springs inside.

Your engine will probably run fine.  Just might gunk up the oil sooner than normal.  We could probably have a whole thread on PCV systems.

[wheee!]

Back to the more mundane tasks at hand, grinding and drilling etc. Metal work begins!

[Consigli]

27 minutes ago, wheee! said:

Back to the more mundane tasks at hand, grinding and drilling etc. Metal work begins!

Do you ever sleep?

[wheee!]

Back to the more mundane tasks at hand, grinding and drilling etc. Metal work begins!

Do you ever sleep?

.... at work