OK now I have an oil question

PAPPY HAROLD

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I have a oil thing that bugs me. When the engine was built evry bearing was checked to keep 2 to 3 thousands clearence, now when I start it it has 65 to 70 psi pressure, but within about 5 minutes it drops to 45, if I hit the gas it jumps right back up.

So do you guys think I have a problem or just the wrong oil? currently running 20-40

 

comanchepilot44

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I have a oil thing that bugs me. When the engine was built evry bearing was checked to keep 2 to 3 thousands clearence, now when I start it it has 65 to 70 psi pressure, but within about 5 minutes it drops to 45, if I hit the gas it jumps right back up.

So do you guys think I have a problem or just the wrong oil? currently running 20-40
Normal operation. When the oil warms up, it thins out. This is the cause of the decrease in oil pressure. I like 20w-50, but you'll see about the same results.

 

marks73

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Nah! Your good.

 

droptop73

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X3 good enough

The oil is a little thick for my taste, I like 10w-30. It flows a littke easier at cold temps.

 

matrixx

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I would drop her down to 10w30 but that's just me. I doubt you would see much difference in the oil psi though. I like to think the 10w30 will get throught the engine quicker on cold starts. depends on your climate though, if your not racing the engine and it's not constantly above 80* yet then i would stay away from anything higher than 40 weight.

Better to have higher pressure than lower pressure.

 

Don65Stang

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Dinosaur oil or synthetic?

Dino oil uses the lower viscosity rating and adds additives to it to get the higher viscosity rating. Meaning the take a 10 wt base oil mix in additives that bump it to 30, 40, 50 wt, etc.

Synthetic is just the opposite. They make the oil to be the higher viscosity as the base, say 40 wt, then put additives in to lower the viscosity to 10 wt.

Personally I use the lightest wt dino oil that still gives me good oil pressure. That oil is usually 5w-20 Valvoline dino oil. When running it hard and hot I still have good pressure so I'm good.

If I have low pressure, then and only then will I start bumping the viscosity up with each oil change until I have good pressure. Say 10w-30, then 10w-40. 10w-30 does the trick though in old, high mileage engines.

 

wwhite72

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My builder specified a zinc added oil, said 10-30 or 10-40 is fine. I use valvoline VR1 10-30 and havent had a problem. I had some strange rhythmic vibration that got worse at higher rpm. Turns out my coil was failing and was losing spark as rpm rose. It became more obvious as time went on. With the new coil it runs great. The 10-30 is fine year round in the NE moderate climate and the hydraulic roller lifters and valve train has been running like a watch. Remember clevelands have been known to have difficulty getting oil to the crank under racing conditions so i figure 30 weight is better than a heavier weight. I do not have the moroso oil kit in my block.

 
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