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Discussion Starter #1
Hope someone can help . I have a 1990 lx 5.0 , I blew a head gasket and dumped a crapped load of water into the oil , well I pulled the heads replaced the head gaskets and opted for a set of GT40P heads from a 98 mountianeer . I flushed the engine pretty good with fresh oil while I had the intake off . When I got it all back together it ran better than ever , with one exception , my oil oil pressure was only running around 20 psi . Prior to blowing the head gasket it was between 42 to 50 psi . So I replaced the main and rod bearings and oil pump and went to 20w50 oil and it jump to around 40 psi , but after running for about 30 to 45 minutes it drops back down to around 25 psi except under accelaration . I strongly suspect the cam bearings , but that is alot of work , does anyone know of a way to get the pressure back up without replaceing the cam bearings and rebuilding the engine ?
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How long did you run it with the blown headgasket?
 

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Discussion Starter #3
longer than i wanted to , maybe 15 to 20 minutes . that's when it tryed to over heat and i caught it . unfortunatly most of the contents of my radiator were in my oil by that point
 

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Discussion Starter #4
i would just like to get the pressure back to a safe level for now so i can drive the car every now and then . i plan to rebuild the engine and transmission soon , but with christmas and a wife and 3 kids sometimes extra money is hard to find
 

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that is a safe level
 

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Discussion Starter #6
i'm use to it running around 40 psi when hot and about 50 psi on start up . I would like to get it back to around that
 

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Discussion Starter #7
I can rebuild the engine for under a thousand , but if i'm going to do all of that i want to swap out the cam , switch to a steel forged crank and keith black pistons . but all of that costs extra .
 

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Maybe it's just me but 40 psi at idle seems a bit high. Your numbers seem fine to me.


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Discussion Starter #9
this is the second 5.0 i have had in this car and the other one ran at about 40 psi hot , and my buddy has a 1993 gt 5.0 and his is running between 38 and 40 psi hot
 

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Discussion Starter #12
Also , forgot to mention when I replaced the fuel pump I did use a high volume pump . But I used a high volume pump on the previous engine with no problems
 

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Discussion Starter #14
Sorry , yes oil pump . thank you . I personally have had better luck with the melling high volume pumps over oe replacements
 

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I would only use a high volume with a 7qt pan


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Discussion Starter #16
As I said , I have always had better luck with the high volume pumps . But any way , does anyone have any ideas on how to raise the oil pressure short of replacing the cam bearings ?
 
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