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Most common cause of crankcase pressure, especially with higher compression, is bad valve stem seals, next is valve guides in addition to stem seals.

Pull the intake manifold off, grab a small mirror, and remove the valve cover. SPray carb cleaner at the valves and see if anything makes it into the intake port
 

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Do like Joe said, increase the breathing of the baffle of the valvecover.

Would not hurt to put a pair of barbs on the exhaust side of the valvecover as well. Run em to the intake tubing or catch can.
 

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Find a hill, run up it all the way, turn around, grab a low gear, run it high into the rpms, then coast down the hill while in gear.


Burp the throttle when you get to the bottom. If it shoots out a lot of smoke, your oil situiation is coming from stem seals or guides.
 

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Its leaking oil, not burning it.
I get that. But any time the valvetrain is able to leak oil into the intake tract, fuel vapors can get sucked in as well, and eat seals up.

Front main seal and camshaft front seal are prime targets for this reaction, and love to leak first. Though technically all rotating surface seals get the axe first when seals/gaskets start to deteriorate
 

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Ooh okay. Sorry for my somewhat harsh reaction. I've posted this issue on multiple forums and most people assume its burning oil, so I've been saying it like 25x already.

I will test it. Cam and distributor seal are fine tho. Seems to only affect the seals in the bottom of the block.
I dont always cover my thoughts or view points. I wasnt bothered at all.

Just trying to spit some ideas from the chaotic mess inside my head, thats all.

And I can be totally wrong, so verification is always recommended lol
 

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If you do not have a leak down tester, next best thing to try, remove spark plugs, spray a bunch of carb cleaner down each spark plug to wash the cylinder walls, drain the oil and refill with cheap but fresh oil, spin the motor over by hand a few times to help prime the oil pump, and do a compression test. Have a battery charger that can do at least 10 amps hooked up. Get the battery fully charged up.

Spin the engine over for 5-10 seconds no plugs, let sit for a minute. Then start testing compression, with a 5 minute breather each cylinder. Note your numbers.

Then pour 1-3 ounces of oil down each plug. Find a way to measure it. Laundry soap cap, make a line, etc... Test compression as soon as possible after the oil goes in. Still give each cylinder 5 minutes to cool down a bit.

Your numbers should be higher if rings are part of the issue. Cleaning the walls prior to doing this removes chance of sticky rings, though will not solve truly gummed up rings.

The oil will cover the gap, and also help account for too large of a piston to wall clearance.
No matter what, the oil ed up compression test will result in higher numbers.


But if you get something like 30psi higher, might be worth yanking the engine apart and checking tolerances again.
 
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