[turchiac]

My recently rebuilt 454 is using about a qt of oil every 200 miles or so. It has weisco pro tru pistons with plasma moly rings. The engine doesn't smoke makes great power and has zero blowby or leaks, also doesn't foul out plugs. The believe the block was decked .010 but not the manifold. For pcv i have the hose going to the front of my edelbrock carb, and a push in breather on the other side. I do have a baffle in my valve cover, although my pcv valve does have a little oil on it. Im stumped as to where this oil is going? Any ideas? Thanks in advance

[DoubleVision]

Are you using synthetic oil?

[turchiac]

Ive used mineral based and synthetic from 5w30 to 20w50

[327NUT]

Did you break the engine in on synthetic?

[turchiac]

No i used Castrol mineral sae 30

[ericnova72]

Have you run it hard yet, or still just babying it?? Rings need a hard load put to them to break them in well, especial the hard ones like plasma moly. Condition will be worse if you didn't have the block torque-plate honed.

Stick it in low gear only, accelerate hard from a 5 mph roll up to about 3/4 of your redline rpm and coast back down using engine braking to slow down and not the footbrake, keep it locked in low gear. Do this 10-15 times and it should seal up.

If you are unsure at that point if it is sealed well remove the PCV from the valvecover and wrap and tie a rag around it so it can still pull a little air and leave it out of the valvecover for a few hundred miles to isolate the problem, this will test if it is pulling the oil from the valvecover. It will show you if your baffle isn't good enough, 75% of aftermarket ones are inadequate.

[turchiac]

Thanks for the repsonses, im going to put the rag on the pcv and leave it unhooked from the valve cover and see what happens. I dont think its the rings cause i have approx 10,000 miles on the engine and have driven it hard on and off, also there is no smoke coming from the exhaust.

[66GMC]

How much blowby is there with that PCV valve pulled out?

[turchiac]

When i pull the pcv valve out and put my hand over the hole there is no air pushing up.

[40forddgc]

Please let me know what you find. I have a SBC doing the exact same thing. I have 400 miles on it and have used two quarts.

[DoubleVision]

Even after cam break in, you should run it on mineral oil until it has 3000 miles on it or better, depending on the ring type and bore finish, ring break in can take a while, and when synthetic`s in it, they won`t break in. Seen a friend do this when his engine was fresh. Broke the cam in on mineral oil, then switched to synthetic. After about 6000 miles the car still used oil, you didn`t see smoke during the day light, but you did at night with headlights behind you. I told him to switch back to mineral oil and run it for 3000 miles, he did and the oil consumption problem was over.

[turchiac]

The first couple of oil changes i used mineral. I tried synthetic once but with it using the oil as fast as it does, it was expensive to continuously top off with $7 a quart oil. Now im using plain valvoline 20w50. The motor uses oil no matter how im driving but on a recent trip from butler pa to buffalo NY on the interstate it sucked up one full quart. I topped it off before i left and by the time the trip was through about 3 1/2 hours later i was down a full quart. I just don't get it

[DoubleVision]

Then it maybe time to look into other avanues. A leaking intake manifold gasket can cause oil consumption. Bad valve guides or missing valve seals can as well.

[turchiac]

Yeah the block was decked, i think .010, would this possibly cause problems with the manifold sealing? I didn't have the manifold or heads milled.

[ericnova72]

That small amount cut wouldn't change anything.

What intake gasket type and brand are you using?