Mass of air in a vacuum.....

mrvette

Phantom of the Opera
Joined
Mar 24, 2008
Messages
15,207
Location
NE Florida
Simple question, but NO Google gives me all this crap sites and pay for referances....fuck that....

the question is to produce a simple assed GRAPH of how much AIR from sea level....what 14 lbs whatever average density.....how much air MASS is contained in a vacuum of whatever pressure, going from ZERO to say a/c evac sucktion...28-29 lbs....

LIke a graph of that relationship....to do with the air pump thingy....

so IF I have a vac reading of say 5 inches suck outta the crank case

here in Florida, what does that do to the air mass in the engine??

so any one can help with a simple graph of some sort would be nice...

fuck google...:confused:
 
Simple question, but NO Google gives me all this crap sites and pay for referances....fuck that....

the question is to produce a simple assed GRAPH of how much AIR from sea level....what 14 lbs whatever average density.....how much air MASS is contained in a vacuum of whatever pressure, going from ZERO to say a/c evac sucktion...28-29 lbs....

LIke a graph of that relationship....to do with the air pump thingy....

so IF I have a vac reading of say 5 inches suck outta the crank case

here in Florida, what does that do to the air mass in the engine??

so any one can help with a simple graph of some sort would be nice...

fuck google...:confused:

"how much air MASS is contained in a vacuum" You kinda lost me here.:huh2:
 
probably something in my old thermo books.

Are you trying to figure out how much resistance to the rotating mass under various vacuum levels? That won't be easy. There may be some dyno data somewhere. Easier to measure than calculate.

A dry sump oil pump gains significant HP they say.
 
probably something in my old thermo books.

Are you trying to figure out how much resistance to the rotating mass under various vacuum levels? That won't be easy. There may be some dyno data somewhere. Easier to measure than calculate.

A dry sump oil pump gains significant HP they say.

OK, so I know we can't get a perfect vacuum, listed at 30" so, what is the relative amount of expected air mass in the crankcase with say 2" then 5" then 10" of vacuum applied to said crankcase.....

I suppose this all has to be done at 200 and then 250f temps just to keep it honest on real world street driving....

what me FINAL question is, where to stop?? if I can get 5-7 inches at cruise in the summer, is that enough to bother with or am I blowing smoke??

if the MASS of air is much less, than maybe I getting close to that figger, or is a steady 10" of vacuum but not over 15" really needed to do the job correctly, and where is the break even point???

in other words, without spend a ton of bux....for suck releif valves, and so forth....what can be expected???

right now, I gutted two OLD PCV valves for the valve covers, paralleled into the suck side of a Ford belt driven pump....output into a hose running free....

so there is ONE 3/8 id hose from each valve cover into the suck side of the pump....

the question is...am I whistling and wishing with just 5-7"?? or what???

I mean if the experiment is a foobar, well so be it, but this got my curiosity up now.....wonder if I can see any differance in the IAC count on the computer for having the pump or not....

for instance...not tried yet...
 
with all this talk of evacuating the crankcase, you guys need to realiaze that normally the pvc system routes that back into the carb to be burned.

That oil and combustion filled air will stink to high heaven. You need to route it some place where you won't breathe it.
 
with all this talk of evacuating the crankcase, you guys need to realiaze that normally the pvc system routes that back into the carb to be burned.

That oil and combustion filled air will stink to high heaven. You need to route it some place where you won't breathe it.

HUmmm....so to take that pump output hose into the airstream of the induction?? interesting thought....but that acts to carbon up as if it was a PVC system....no?? more oil on the tbody/blades....

I think to do a hose out the rear of the car....

thing about stockish PVC is that it puts the crankcase under NO sucktion, normally...but...

I remember some time ago frustrated by some RTV somehow not sealing the rear of the intake mani....so I got thinking...how to get the RTV in there...so I hooked up TWO PVC valves to the line..one each cover....when it went negative, I squirted in a dap of carb cleaner, the dapped in a bunch of RTV and killed the engine till morning....it worked....

so the wonder now is....how about using the intake vac and running two PCV valves with a vacuum suck relief?? but then the engine under load at WOT has NO induction vacuum either....

so the crankcase goes positive and back to loosing HP....

cant win....

back to drawing board....anyone on some graph showing air mass at various vac readings....??assuming sealevel....FLORIDA as a starting point??

:stirpot:
 
Top