1970 Chevy V8 oil usage

[jtwoods4]

I have a 1970 Chevy 350 that came from a 1970 Impala. It is currently in my 1968 Camaro. The engine has around 3500 miles on it since the rebiuld. Here are the engine specs:

it is a 4 bolt main 350 bored .030 over it has new flat top pistons, reconditioned rods, polished std/std crank, double roller timing chain with a Summit Racing 1102 cam. The heads are "441" castings with all new guides, multi angle valve job & springs. The intake is an Edelbrock performer, with a 600 Holley carb and an new HEI ignition

There are no oil leaks and no smoke from the exhasut

Question:
I have to add about 3/4 quart of oil every 900 to 1000 miles. Is this normal for an older model 350 even though it is not leaking oil and all the gaskets are good?

[nitrowarrior]

That's not normal or even close.
Who seated the rings?

[R Pope]

Yep, the rings didn't seat. Warm it up, and run it at 2500 RPM for a while, it will probably make visible smoke then. Or run it at highway speeds, then let of the gas until you are down to 30 or so. Boot the gas and watch out back, a big puff of smoke means bad rings. Either live with it, or re-ring it and break it in right. BTW, what oil are you running? Synthetics won't let the rings seat. Break-in should always be done on dinosaur lube.

[jtwoods4]

Yep, the rings didn't seat. Warm it up, and run it at 2500 RPM for a while, it will probably make visible smoke then. Or run it at highway speeds, then let of the gas until you are down to 30 or so. Boot the gas and watch out back, a big puff of smoke means bad rings. Either live with it, or re-ring it and break it in right. BTW, what oil are you running? Synthetics won't let the rings seat. Break-in should always be done on dinosaur lube.

The car does not have any visible smoke, runs fine, there are no leaks. Does this still mean the rings have not seated. I purchased the car with 1500 miles on the engine and then drove it back to my state across country, which was another 1400 mile road trip. I am using regular old Penzoil 10-W40.

[nitrowarrior]

On rare occasions, the rings may eventually seat. If so, it will take a while with constant driving at varied loads.
You could have other issues such as loose piston to wall clearances that promotes oil loss.
Chances are, your rings are not going to seat properly.
Suggestion; re-ring time.

P.S. Poorly seated rings won't always smoke and yet they consume oil so the tale tell signs aren't always the best indicators.

[jtwoods4]

On rare occasions, the rings may eventually seat. If so, it will take a while with constant driving at varied loads.
You could have other issues such as loose piston to wall clearances that promotes oil loss.
Chances are, your rings are not going to seat properly.
Suggestion; re-ring time.

P.S. Poorly seated rings won't always smoke and yet they consume oil so the tale tell signs aren't always the best indicators.

I just talked to the guy that biult the engine and he said that sometimes it can take 3000 to 5000 miles before the rings seat. I guess they will seat soon. I have been driving the car at various loads, a few hard accelerations and some city and highway driving. It will probably seat soon. I hope.

[ted dehaan]

well once upon a time many many moons ago I had one that did the same thing took me along time to figure it out it was the fuel pump seal putting just enough fuel into the crankcase to thin the oil enough to burn it and you could not see it in exhaust changed the fuel pump and oil and filter and never burned another drop of oil between 3000 mile oil changes just a thought ....ted