Compression test

Hey guys. I have been losing oil. I have 3 leaks I know of. Oil pan. Cam seal and valve cover. However they aren't leaking to the point where I lose 2 quarts. So I checked my compression and here they are
cylinder 1 dry:160 wet:160
Cylinder 2 dry:160 wet:200
Cylinder 3 dry:180 wet:200
Cylinder 4 dry:180 wet:300

I have no idea where cylinder 4 has so much compression. My car also doesn't smoke blue. I am running a bit lean though. So that's the only smoke coming from it. I have a ls with a 98 (I think) b20.
So the question really is where is my oil going (rings seals or quides). And why did my compression jump.

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#4 is likely a result from TOO MUCH oil. It shoots up in the compression tester then you're basically compressing the liquid not the gas and measuring that. And if it goes too high you can break your compression tester. Make sure your tester rests at 0psi in free air.

Run the engine for a few seconds, get it back up to temp and redo it. Dont add so much oil this time.

And in regards to #1. Redo that as well just for a sanity check. If the wet test is the same as the dry reading that means you are NOT losing compression by way of the piston ring and by process of elimination that leaves the valves as the culprit. Since 160psi is not THAT low I would assume its NOT a bent valve but possible a poor valve seal caused by either carbon etc.

Thanks for the reply muckman. What's the normal compression on these? And I will do what you said in a few

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I dont know stock engines actually. I used to get 180-190psi on my old built engine when it was 9:1 so Id say you're in the ballpark.

Okay so all are at 200 now but cylinder 2. Cylinder 2 is at 180. And wet it's at 200.

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all at 200 dry? You're not getting consistent results.

Should be 180 dry I believe. Give or take 20% of highest number.

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It's a brand new gauge. Cranked it for 3 seconds with throttle blocked open. I'm not sure if it's me, the car, or the gauge

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The gauge should spike roughly 6-8 times before you release the key. That's how we did them in class.

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The first time I didn't have anyone to start the car so I was running back and fourth. So I feel like the second numbers are the ones I should go by. But then where's my oil going.

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Before I took my motor out to rebuild it had 195-200 in every cylinder. If you're in 180-200 that's pretty good compression I think

Where could my oil be going then? The oil pan is a very very slow leak. So I don't know.

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How's the gasket? Do you know if you're getting blue smoke indicating piston rings or valve seals?

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No she doesn't smoke at all

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If you have no smoke, and your cars getting 180 dry.

I'm pretty sure your where you want to be.

You also stated you have a b20, assuming its a USDM b20 with 8.8:1 CPR

It reassures me your oil rings are holding up.

The 9.2:1 CPR in the USDM b18b/a is suppose to get 200 psi dry is it not?