question on breathers and temp gauge

[BigBlockBaja]

Got my new valve covers from Jegs on my motor. I punched one hole for a pvc. Do I need to punch another for a breather? Can I leave it just like this? Thought that was the idea of the pvc, to create a vacuum in the crankcase. And is there a difference in sending units between Ford and GM temp gauges? I know they differ in fuel sending units by having different ohms. Just wondering becuase I got my new t sat kit installed and it doesnt read any temp at all, but the motor is warm.
Thanks,
Pat

[Rexone]

All sending units must be the correct match to the particular gauge being used whether it be autometer, faria, vdo, whatever. They are all calibrated a little to a lot different. Wrong sender = wrong or no reading.

[BigBlockBaja]

Thanks Rexone. The boat had a sbc but i got a deal on a BBF (free) and in the process of hooking up the "little things"

[Chris J]

My .02 (Although this is a good question for debate)
The purpose of the PVC is to reburn any gases that blow by the piston rings. It also help to reduce oil leaks around the crank seals by creating some vacuum. IMO you should run a breather with a pvc valve. The sudden changes in vacuum when you let off at higher rpm can suck in your intake, oil pan and other gaskets. Also it fights your oil pump dropping your oil pressure equall to the vacuum it creates.
It's not uncommon to use vacuum pumps to create horse power, but it's more of a constant vacuum based off rpm not throttle position. With a PVC valve you would make little vacuum at WFO and huge vacuum once you let off, which would be ass backwards of what you want.

[mgar_red]

PVC = PolyVinyl Chloride (plastic stuff)
PCV = Positive Crank Ventilation (valve)
:D

[Chris J]

Hey, so I'm a fat fingered dyslexic... cut me some slack. :D

[BigBlockBaja]

PVC = PolyVinyl Chloride (plastic stuff) Didnt mean to make a refrence to that. Opps.. I think just to play it safe, im going to see what comes of this thread and go from there, But I agree with ya chris. Im leaning toward ordering a breather soon.

[BigBlockBaja]

DOH!!!!!!!! I was thinking of pcp.. me = dumbass :D :D

[Moneypitt]

Look at your car....The PCV valve is plumbed into one side, and a tube attached to the air cleaner goes to the other. The one from the air filter is an "inlet" to the crankcase. If you look inside the A/F housing you will see that that air is allowed into the engine AFTER it passes through the airfilter. This inlet allows the PCV valve on the other side to draw air through the engine, which also draws oil vapor, unburned fuel that makes its way into the pan, etc. Running just the pcv valve won't work. It won't really create any real problems other than not working, but for proper operation you will need a breather of some sort on the other valve cover. On a boat, you don't need to pass inlet air through your a/f because there isn't alot of dust on the water. The misconception that the tube to the a/f is an additional vent is because when the rings are excessively worn, the pcv can't keep up and the oil vapor finds its way out anyway it can, and puddles oil inside the a/f housing. I use a standard push in breather on one cover and the PCV on the other. You can use the push in breather as a place to add/fill oil into the motor......Moneypitt