1976 280Z Restoration Project

[Hodgimus-maximus]

You also have to keep in mind that most oem fuel injected cars don’t use a map sensor, they use a mass air flow meter.  Most after market ECU have the option of just using 4 variables to regulate fuel delivery; Map pressure, rpm, O2 sensor.  

There are also two other sensor that modify fuel delivery which are, inlet air temp sensor, and coolant temp sensor. 

By not using a mass air flow meter the car will tolerate air leaks that aren’t directly connected to the manifold better.

All the ECU is doing is saying for this map pressure and rpm I will deliver this much fuel. 

[Zed Head]

I think that we're just disagreeing on levels.  It's a matter of degree.  Tolerating and running clean aren't the same.  Many of us have felt that our engines run just fine but they won't pass emissions.  The system tolerated the dirty coolant sensor connections or high fuel pressure or whatever the problem was.

I like what wheee! is doing but there is a small bit of irony in having a catch can to keep the oil out but possibly running rich at time and carboning up the combustion chamber. 

But, it's a matter of what you want.

The whole point of EFI was to be cleaner.  Carbs worked fantastically, but were dirty.  Good old Holley double pumpers, squirting loads of extra fuel whenever you hit the pedal.  I can nasalize the smell...

Edited July 30, 2019 by Zed Head
dong in an uncomfortable place...

[Captain Obvious]

My understanding is that the PCV valve is a metering device. It's not a wide open leak.

And if you're not running any sort of air flow meter and are getting all your loading info from a MAP sensor, then I'm not sure it matters.

[w3wilkes]

4 hours ago, wheee! said:

The FI cars send the air from the valve cover back to before the throttle body so the air coming in gets metered along with the fresh.

I agree Zed. I am not disputing how things should work. I keep hearing how the airflow balance from the valve cover is negligible, but obviously it was significant enough to have Nissan engineer it into the throttle body air flow. Maybe that was also part of the environmental concerns at the time to ensure oily gases got recirced.

It would be no big issue at all for me to recirc it into the air intake before the throttle body. It would just add an unsightly hose to the top of the engine which I was trying to avoid. I also have a valve cover, if anyone remembers, that has the vent facing the firewall at the back of the driver side of the valve cover. That one is chromed.

On a carb'd car the air is dumped into the back plate of the air cleaner so the air going into the carb from both the valve cover and fresh is also "metered" since it is dumped to the air cleaner before going down the throats. And I believe this was done on these cars also to address the oily gases getting recirced for environmental concerns.

Edited July 31, 2019 by w3wilkes

[Zed Head]

7 minutes ago, Captain Obvious said:

not sure it matters.

Depends on what your "matter" criteria are.

This sub-discussion is really just about people's  opinions of how they like their engines to run.  But the PCV valve is an interesting thing.  Why are there are so many models of them?  They all look about the same.

 

[wheee!]

Tonight I filled the transmission with 80w90 for the first fluid run through the cleaned tranny. I will dump it for the good stuff along with all the other fluids in the first 100kms.

Then I went back to the throttle cable and got it figured out.
The cable runs under the heat shield about an inch from the headers. Not great but it is a stainless shielded cable.
Then it exits the heat shielding into a custom roller wheel to guide it up to the Borla 70mm throttle body.
I haven’t cut the cable yet but used a clamp for temporary testing.
Spoiler... it works great!!

[wheee!]

The Haltech uses the following sensors:
Idle Air Controller valve
Water temp sensor
Intake Air Temp sensor
Oil pressure sensor
Wideband O2 sensor
Crank Angle Sensor
MAP sensor

I’m pretty sure the control I’m going to have over literally everything else will give me better performance if not a slight amount of unmetered air or blowby.

[wheee!]

I know this is not everyone’s idea of what an engine bay should look like, but I am really liking how it’s coming together. For a weekend cruiser/show car, this will achieve my driving goals as well as my aesthetic idea of what a performance restomod should look like.

[w3wilkes]

7 minutes ago, wheee! said:

I know this is not everyone’s idea of what an engine bay should look like, but I am really liking how it’s coming together. For a weekend cruiser/show car, this will achieve my driving goals as well as my aesthetic idea of what a performance restomod should look like.

I think it looks fantastic! The red "highlights" are a great splash of color in there too. South of you down here in Utah where me and my 240Z hang with the local hot rodders they have a saying... "If the part don't go, chrome it."

Edited July 31, 2019 by w3wilkes

[wheee!]

Finished the throttle linkage.
I drilled and tapped a fitting so that the cable could run vertical and be adjustable. This was locked in place with a cable set screw.
I then solved the riddle of what to do with the old linkage tabs! I added a return spring helper to make sure the throttle snapped back nice and tight.
A quick pedal height adjustment and I now have full range of motion from idle to WOT! [emoji2]

[wheee!]

[w3wilkes]

Darn it! At first I thought we were  going to hear it "sucking". Sure looks like it's a nice and smooth action. Super nice work!