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here this will help


http://www.babcox.com/editorial/us/uhs89734.htm

http://www.thirskauto.net/BearingPics.html


http://www.babcox.com/editorial/ar/ar20128.htm

http://www.babcox.com/editorial/cm/cm99828.htm

http://www.thirskauto.net/Engine_Thrust_Bearings.html

http://www.aera.org/tech/tb1465r.htm

http://www.aptfast.com/Flyer_HowTo_Dir/HowTo_Folder/Cam_Bearing_Install/Install_Cambearings.htm

http://www.dragnbreath.com/Clevite/TN 28cambrgs.html

http://www.diabolicalperformance.com/clearances.html

http://www.jimcookperformance.com/TechNotes/TN 28cambrgs.html

http://www.babcox.com/editorial/ar/ar10180.htm

http://www.babcox.com/editorial/us/uhs69720.htm
ok lets look at a few things, pressure is the result of a resistance to flow , no matter how much oil is put out by the oil pump there is almost no pressure unless there is a resistance to that oil flow and the main resistance is from oil trying to flow through the bearing surface clearances and once the pumps output pressure exceeds the engines ability to accept the oilflow at the max pressure the oil return system/bypass spring allows the oil circles back through the pump , yes its possiable for the crankshaft WITHOUT A WINDAGE SCREEN to keep acting like a propeler and pulling oil around with it in the crank case but thats what the wrap around style milodon type windage screen is designed to stop)the only way to run out of oil is to start with less than 4 quarts or to plug the oil return passages in the lifter gallery with sludge or gasket material! now add a good windage tray and a crank scrapper and almost all the oil is returned to the sump as it enters the area of the spinning crankshaft! forming a more or less endless supply to the oil pump,
NOW I POSTED THIS BEFORE BUT IT NEEDs REPEATING
ok look at it this way,what your trying to do here is keep an pressureized oil film on the surface of all the bearings to lube and cool them and have enough oil spraying from the rod and main bearing clearances to lube the cam and cylinder walls/rings. now a standard pump does a good job up to 5000rpm and 400 hp but above 6000rpm and 400hp the bearings are under more stress and need more oilflow to cool and because the pressure on the bearings is greater you need higher pressures to maintain that oilfilm.lets look at the flow verus pressure curve. since oil is a liquid its non-compressable and flow will increase with rpm up to the point where the bypass circuit starts to re-route the excess flow at the point were the pressure exceeds the bypass spring pressure. but the voluum will be equal to the pumps sweep voluum times the rpm of the pump, since the high voluum pump has a sweep voluum 1.3-1.5 times the standard pump voluum it will push 1.3-1.5 times the voluum of oil up to the bypass cicuit cut in point,that means that since the engine bearings leakage rate increases faster as the rpms increase because the clearances don,t change but the bleed off rate does that the amount of oil and the pressure that it is under will increase faster and reach the bypass circuit pressure faster with the high voluum pump. the advantage here is that the metal parts MUST be floated on that oil film to keep the metal parts from touching/wearing and the more leakage points the oil flows by the less the voluum of oil thats available for each leakage point beyond it and as the oil heats up it becomes easier to push through the clearences.now as the rpms and cylinder preasures increase in your goal to add power the loads trying to squeeze that oil out of those clearances also increase. ALL mods that increase power either increase rpms,cylinder preasures or reduce friction or mechanical losses. there are many oil leakage points(100) in a standard chevy engine.
16 lifter to push rod points
16 pushrod to rocker arm points
32 lifter bores 16 x 2 ends
10 main bearing edges
9 cam bearing edges
16 rod bearing edges
2 distributor shaft leaks
1 distributor shaft to shim above the cam gear(some engines that have an oil pressure feed distributor shaft bearing.)
so the more oil volume the better as long as that oil flow is totally under control, and that will in most engines require both a baffled oil pan and a windage screen correctly installed in a block with clear oil drain back holes if the engine is going to be run a high rpm levels, changes in the oil pump pick-up location in the oil pan of only about 1/8" are sufficient to noticably effect the efficientcy of the pumps abillity to effectively control/supply oil

BTW,YOU CONTROL the volume of oil flowing thru your engine to a great extent when you set up the ENGINEs BEARING CLEARANCES, and you CONTROL the rate of oil flow back to the sump by checking that all the drain back holes are clear and by useing a milodon style windage screen properly mounted about 1/8" from the spinning crank assembly, the oil pump pick-up mounted about 3/8"-1/2" off the floor of the oil pan and by useing a properly designed oil pan with matching oil pump pick-up. the greater the voluum of oil flowing over the bearings the more heat can be carried away and the more constant the surface temp. can be. and before someone jumps in with that old myth that oil flowing over the surfaces to fast will fail to pick up the heat from the bearings let me point out this chart





bearing clearances larger than about 1.5-2 thousands tend to flow more oil than necessary, making the oil flow back to the sump harder to control.
I started out with a Z-28 sbc oil pump, It failed to supply the needed oil volume in my racing engine, I swapped to a high volume sbc pump with 1.5" pump gears and it worked OK , but still failed to build pressure fast enough to meet my needs, now before you get any incorrect ideas, understand that a full racing ,(road racing engine) has several mods to inhance lubracation and needs extra oil flow, to keep the bearings cool durring some races that last HOURS not seconds like in drag racing, heres a few of the mods
The bottom of a Chevrolet distributor housing can be modified to spray pressurized oil onto the distributor drive gear. The extra lubrication will reduce distributor gear and camshaft gear wear. This is especially important when the gear is used to drive non-standard accessories, such as a high volume oil pump, or a magneto that puts additional loads on it and the cam. When the distributor is installed, the bands at the bottom of the housing are designed to complete the internal right side lifter galley on all small and big block Chevrolet V-8 and 90° V-6 engines. If you hand file a small vertical groove .030" wide x .030"( thats the diam. that crane recommends Ive always used the larger groove with no problems deep on the bottom band (above the gear), pressurized oil running between the two bands will be directed downward onto both the gear and the cam. This procedure is recommended for all Chevrolet engines no matter what material gear (cast or bronze) or what type of camshaft (cast or steel) you are using
keep in mind the groove MUST be lined up with the cam gear when the distrib. is installed , this tends to prevent cam/distributor gear wear

also read this because the quality of the oil you use also has a big effect on how your engine wears during its lifetime. http://www.micapeak.com/info/oiled.html

REMEMBER WHAT YOUR TRYING TO ACCOMPLISH IS THE TOTAL PREVENTION OF METAL TO METAL CONTACT, AND ONLY THE BEST ANTI-WEAR LUBERICANTS PLACED BETWEEN CONTACT SURFACES AND FLOWING INTO THE CLEARANCES CAN DO THAT !
BTW DON,T FORGET TO PRELUBE THE ENGINE WITH AN ENGINE PRELUBER WHILE TURNING IT OVER BY HAND UNTILL OIL FLOWS FROM ALL THE PUSH RODS ONTO ALL THE ROCKER ARMS BEFORE http://www.dorianyeager.com/oilfilterstudy1.html
http://www.micapeak.com/info/oiled.html
, add a can of G.M. E.O.S. to the oil(G.M.part #1052367 )

ENGOILSUP

EOS - Engine Assembly Prelube
Specifically formulated as an engine assembly lubricant. E.O.S. provides outstanding protection against run-in wear and piston scuffing as well as run-in camshaft lobe and lifter scuffing resulting from insufficient lubrication.)

- BTW I always stick four of these magnets in the corners of the oil pan sump , you will be amazed at how much metalic dust they pick out of the oil and keep from getting to your bearings,(either one works fine)
http://www.wondermagnet.com/dev/magnet2.html
http://www.wondermagnet.com/dev/magnet42.html

or

http://www.wondermagnet.com/dev/magnet1.html


and I put one in each corner of the oil pan sump and 2 more in the other end of the oil pan these WILL CATCH ANY IRON DUST IN YOUR ENGINE!!

http://www.compcams.com/catalog/335.html
and read this


http://www.melling.com/engoil.html

http://www.melling.com/highvol.html
 
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