Hi there, I'm building a 6 port 13b dellorto setup with a atkins wrap around intake and keeping the omp

Was wondering if the vac lines coming off the oil injectors are vac or are they pressure?

Im only asking because it makes more sense that the oil injectors would have air blowing in to them then having air sucked out.

Any help would be appreciated.

Thanks

 

you already know.

 

They are neither vac nor pressure, but fresh air. They lead to before the throttle plates.

So I guess, pressure as the engine is under vacuum.

 

Thanks for the info. I appreciate it.

 

If the OMP vacuum lines are plumbed into the intake tract before the throttle body, that would say they require Constant Vacuum. Try putting your hand, or a piece of paper on the intake tract and see what happens.

On a turbo engine, they are plumbed into the turbo inlet duct as found on the FD's vacuum diagram. The FC, and both 13B-RE and 20B-REW Cosmo also are plumbed this way too. They are the dark blue lines shown here:
https://www.rx7club.com/3rd-generati...-turbo-749702/

If the OMP injectors were plumbed into the intake manifold on a turbo engine, the manifold pressure would attempt to push the oil back down the OMP lines, yielding an oil-starved engine.