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I have been told that high pressure pumps can starve your main and rod bearings by pushing too much oil to the top of the engine hence creating friction and ruining your bearings. I was told that a stock pressure pump was the way to go on a 440hp 383 stroker that i am building-hmmmm???? Now, i know that the higher rpms you turn that the more pressure you need to get the oil out through the crank and to the bearings due to the increase in centrifugal force. What do you guys that have built some high hp engines before think?? I am really not sure which to use and of course i don't want to starve my bearings. Should i enlarge the crank bearing holes like some of the engine building books suggest-it is a brand new scat crank and i would hate to slip and mess up the journal surface.
 

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As long as the bearing clearences are up to snuff, I would just run the stock pump. There isn`t really much danger in running the high volume unit, as I`ve ran many of them in past engines and never had any problems, these were lightly modified street engines and it really didn`t need it, it only robbed the engine of horsepower. As for the crank I wouldn`t flare the oil holes, I would just clean and deburr them.
 

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65vettestroker said:
I have been told that high pressure pumps can starve your main and rod bearings by pushing too much oil to the top of the engine hence creating friction and ruining your bearings. I was told that a stock pressure pump was the way to go on a 440hp 383 stroker that i am building-hmmmm???? Now, i know that the higher rpms you turn that the more pressure you need to get the oil out through the crank and to the bearings due to the increase in centrifugal force. What do you guys that have built some high hp engines before think?? I am really not sure which to use and of course i don't want to starve my bearings. Should i enlarge the crank bearing holes like some of the engine building books suggest-it is a brand new scat crank and i would hate to slip and mess up the journal surface.
High pressure or and volume seem to say ,, ..
The more oil (lubrication in the right places at all times )
is only going to work iff you steer it to the spots that need it when they need it ,,,
 

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you don't need a HPHV pump. Its going to rob about 5-10 horse off your motor because its tougher to turn. I've seen 650 horse strokers run stock pumps, chevy has good oiling to start with. HPHV pumps are for cars that are turning very high RPM for a long time, and its kinda pointless to get one unless you set up the motor to use it (hog out the galleys, touch up the bearing clearances etc).

in your motor there's probably about a half of a cup or less oil doing lubrication at any given time. Don't go overkill, you won't help a micron of metal in your engine by going HPHV (in fact you're running risk of wearing your cam and distributor gear more quickly)

K
 

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Chevy put more priority on their mains. A stock pump will be fine at the crank.

I run a high volume high pressure pump. I would recommend them for 400s, but not for 350s.
 

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I'v never ran over 50 pounds of pressure in our Circle track engines. We open up the returns and use mobile 1 full syn. Never had a oil related problem all year long. You don't need higher pressure, ever. Enough to keep it in the throws but no more. Any more than and you waste good power and over heat the oil.
 

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Oil Pumps

I agree with everyone too! A stock oil pump will give you all the volume you need. And as stated running Mobil 1 synthetic oil just assures you of good oiling protection. My opinion too much oil pressure causes problems.
 
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