I've got a four bolt main 350 that eats oil pretty bad. After a fresh oil change, I have to pour in a new quart every week and a half to two weeks to maintain oil pressure. The engine is a recent rebuild (albeit a very cheap quickie local job) with less than 15k on the clock. I needed the engine immediately to get the car going, and I know it was a pretty crappy build cuz it won't make decent pressure unless it's full of at least 40 weight (temp NEVER falls below 77 in Miami). My question is, is there anything I can do other than a proper rebuild to cut down on the oil consumption?

 

LEARN.
Then measure, measure, measure next time.
Does it have excessive blowby?

 

If you didn't drive it, oil consumption should nearly cease.

I know that doesn't help, but it sounds like you already know the solution.

 

it doesnt appear to blow by once it's warm, but you can see it until then. It's gotta be getting burnt through the engine tho; there are no leaks. im afraid i can't just let it sit, either. the car's my daily. i was hoping for some miracle additive or something. i'd hate to bomb a good four bolt block because i dont have the time or the cash to rebuild it.

 

A weekend with the engine puller and some new rings probably would do wonders. Don't forget the dingleberry hone!

 

Has the oil consumption been a problem ever since the rebuild? I'm concerned that either the rings were never properly seated, or the intake may not be sealing. There is also a chance (depending upon your heads) that the rocker studs are leaking oil from the valve spring area to the intake runners.

Leaks in the intakes may allow oil mist to be drawn from the lifter valley and burned. Red Devil may be onto something (we've always suspected that). Spending a day pulling the intake to make sure the gasket impressions indicate a good seal might be worth the time. If there is very little overlap at the lower intake flanges, it could be a problem. With the intake removed, you'll also be able to see if there is oil dripping from the rocker studs. Many heads have no material sealing the bottoms of the studs. The stud holes are drilled straight through into the intake port runners. If no sealant was used on the studs when they were installed, that could account for oil consumption.

 

i'm pretty sure the heads are in decent shape; i assembled them myself. im inclined to suspect than it's less than stellar ring seal. i bought the shortblock from a local machine shop. i've had more than a few problems with them, including a stripped out crankshaft bolt. if i decide to re ring the motor, I might as well put some more appropriately sized bearings in while i'm at it, right?

 

if the bearings are the wrong size now, you're hooped.
If you're going to pull the motor and do a full tear down, give yourself a few days, and some help. You don't want to rush it, and make it worse. Some plastigauge will let you know if you're holding the right bearing size. If the bearings are ok, re-use, if not, yea, buy new ones in the same size. (Plastigauge the old ones to make sure that's the size you want).