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Id need to point out that the differance between a standard and a high pressure pump is usually only the resistance in the bye-pass springs resistance, standard pumps generally have bye-pass springs that allow the bye-pass circuit too open at about 60psi-65psi
HIGH PRESSURE pumps generally have bye-pass springs that allow the bye-pass circuit too open at about 70psi-75psi
SPRINGS CAN BE SWAPPED!

http://forum.grumpysperformance.com/viewtopic.php?f=54&t=3536&p=9372#p9372






http://users.erols.com/jyavins/solder.htm
http://www.tinmantech.com/html/faq_brazing_versus_soldering.html

THE QUICK WAY TO IDENTIFY THE DIFFERANCE BETWEEN THE BIG BLOCK PUMP AND
THE SMALL BLOCK PUMP IS THE SMALL BLOCK PUMP USES A 4 BOLT COVER AND SMALLER 7 TOOTH GEARS AND A 5/8" FEED TUBE FOR THE PICKUP
THE BIG BLOCK PUMP IS THE BIG BLOCK PUMP USES A 5 BOLT COVER AND LARGER 12 TOOTH GEARS AND A 3/4" FEED TUBE FOR THE PICKUP


THE DIFFERANCE BETWEEN A STANDARD VOLUUM AND A HIGH VOLUUM PUMP IS THE TYPE AND LENGTH OF THE IMPELLERS, BELOW THE IMPELLERS LENGTH IS SIMILAR, LONGER IMPELLERS AND LONGER PUMP BODIES ARE AVAILABLE




braze the pick-up tube to the pump body so the pick up is 3/8" MINIMUM, 1/2" maximum from the oil pan floor and use a large lump of MODELING CLAY (every mechanic should have some its great for checking clearances)on the pickup then install the pan temp. with no gasket and remove to measure the thickness of the clay
your local arts/craft store sells it in 1 lb blocks I usually use brite blue or black but suit your self, a digital caliper or even a ruler will get you the thickness measurement your looking for)

http://store.yahoo.com/teacher-parent-store/modelingclay.html

http://www.guildcraftinc.com/ProductInfo.aspx?productid=102-500

once its correctly possitioned ,remove the bye pass spring and gears from the oil pump,and have the pick-up brazeD or welded to the pump body, then after it SLOWLY AIR cools (DON,T DROP IT IN WATER LET IT AIR COOL)replace the byepass spring and gears, lube the pump,with assembly lube on the gears, check the clearances, check clearances again! and install! just be damn sure its brazed or welded in the correct location as that 3/8"-1/2" is critical to good oil voluum feeding the pick-up
http://www.epemag.wimborne.co.uk/solderfaq.htm

silver soldering is basically lower temp brazeing , the soldering metal flows over the surface and into micro cracks in the surace of the other metal forming a almost unremoveable bond to the other metals surface it allows you to stick iron to steel or brass to steel, it works more or less like normal solder does on copper but at higher temps and has a much stronger grip in addition too working on iron and steel
I vastly prefer the 5 BOLT BBC style pumps with the 12 tooth gears and thier larger 3/4" pick-up VS the small 4 bolt pumps with thier 5/8" pick-ups and 7 tooth gears. the oil flow is both higher pressure at low rpms and smoother in pulse presure spread,no! you don,t need it on a non-race combo, or even on some race combos but its nice to have and I willingly will loose a few hp pumping oil for better engine lubracation
YOU DON,T NEED OR WANT A BBC OIL PUMP on a MILDLY MODDED ENGINE, unless youve done a good deal of oil control mods , TO CONTROL THE EXTRA OIL, YOU DON,T WANT THAT MUCH OIL PRESSURE OR FLOW, and theres NO NEED FOR it in a basically stock engine or MILDLY MODDED ENGINE,


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 voluum the better,(AS LONG AS ITS TOTALLY UNDER CONTROL ON BOTH THE PRESSURE AND RETURN/SCAVAGEING SIDES OF THE SYSTEM



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-.050" wide x .030deep thats the diam. that crane recommends Ive always used the larger .050 x .030 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 installedmoving the distributor timing moves the oil spray pattern area so the time taken too CAREFULLY CUT a second shallow grouve in the block , on the lower band where the distributor seats and seal the oil passage as a secondary extra presureized oil spray source spraying oil onto the gear contact area,that can,t move seems like an even better IDEA . having twin high pressure oil jets spraying oil into the gears helps slow potential wear
you file a groove in both lower bands about .050 wide x.030 deep directly in line with the cam gear when the distributor is in its installed position, youll need to get the car started and timing set then mark the distributor, pull it and correctly cut the groove in the possition to spray a constant stream of oil onto the contact area of the steel cam to bronze dist. gears contact point.
BTW
drilling a .032 hole in the lifter gallery plug behind the cam gear will also help the life of the chain by getting more oil to it when the engine is running
 
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