Vacuum

[ProTechAutoServices]

Hi, I'm building a old school 5.0l engine, with a gt40p heads and gt40 intake manifold. My question is....Can I run the vacuum hose under the intake manifold straight to the pcv valve or I still need to use the by pass under the intake manifold. That by pass is actually hitting the valve cover ; the cover are not the factory ones, they are toller than the original. I know I can use some spacer on the intake manifold, but I'm wondering if I can do that, thanks.

 

[General karthief]

Yeah, not much room under there with tall valve covers, I guess you could plug them two off and hook to a vac source by itself, I don't know what effect it would have t'd into the main supply to the vac tree. You could thread a nipple into the core plug at the back of the upper, maybe use a 90* nipple pointed down to clean it up.

 

[Noobz347]

Post an image when you have the chance.


If I am understanding your question correctly then, "Yes". You can plug the the PCV hole in the back of the intake and use another vacuum source to run the PCV valve.

However, lots of folks have just done away with the PCV system altogether and just vented the valve covers.

 

[General karthief]

Speed dencity or mass air computer?

 

[ProTechAutoServices]

Mass air

 

[ProTechAutoServices]

Speed dencity or mass air computer?

Mass air

 

[ProTechAutoServices]

Post an image when you have the chance.


If I am understanding your question correctly then, "Yes". You can plug the the PCV hole in the back of the intake and use another vacuum source to run the PCV valve.

However, lots of folks have just done away with the PCV system altogether and just vented the valve covers.

 

[Noobz347]

Ok... The port you circled in yellow. If that is the one you want to eliminate then yes... eliminate it.

You can use the port from the center section and route the hose how you want for the PCV.

The image you have circled in black should have one just like it in the upper plenum. If so, you really don't need to do anything with that. If the upper plenum doesn't have it, the gasket will seal it.


Edit:
Later versions of that same manifold had a simple "L" vacuum fitting in that location (circled in yellow) exactly like the one on the opposite side.

 

[ProTechAutoServices]

Ok... The port you circled in yellow. If that is the one you want to eliminate then yes... eliminate it.

You can use the port from the center section and route the hose how you want for the PCV.

The image you have circled in black should have one just like it in the upper plenum. If so, you really don't need to do anything with that. If the upper plenum doesn't have it, the gasket will seal it.


Edit:
Later versions of that same manifold had a simple "L" vacuum fitting in that location (circled in yellow) exactly like the one on the opposite side.

Thank you