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On another thought. My 48 custom 8 is a bit of a smoker. I have had the valves adjusted but would love to have the rings replaced. Can I get that done without pulling the engine? I was thinking maybe they could loosen the motor mounts and then dropping the pan. But I am not sure that could be done. It is so much easier to ask before I jump into the snake pit. You all have saved me many times in the past I just thought I would ask.

Of course it can be re-ringed without pulling the motor, that was a pretty standard operation in the day on higher mileage engines. Did my 48 Custom 8 that way some years back. Ridge cut, pistons and rods removed, honed the cylinder walls (very minimal taper), new rings, wrist pins & bushings, con rod bearings, etc. All from above/below with the block in the car. You might also consider installing piston skirt expanders or knurling the skirts if the pistons don't need replacing but the clearance is a bit out of spec.

If the piston ring grooves are not badly worn, it's just a matter of replacing the rings. If the groove wear is too much the new rings will break in short order, then you can have the grooves recut to an oversize and use piston ring spacers. This also was a pretty common operation.

If the engine is really high mileage, you can go a lot futher with the engine in the car. You can remove the cam, have it and the cam followers polished, replace main bearings and front and rear seals, and more. Did all that on mine as well at the same time.

What you can't do with the engine in the car is bore the cylinders or turn the crankshaft. If they are OK and the crank is round and without scoring you can do a pretty complete semi-overhaul engine job. That was the stock in trade of many dealers and auto repair shops.

Thanks for the information. I would say that my engine doesn't have that many miles on it. The one in the car only had 27K but the gal that had it in storage didn't understand how to keep a block from having a 12 inch crack. YUG. So I had to get another engine and it had sat also for years. So in the beginning it smoked a lot but now not so much.

This used to be known as a ring and valve job and was common when your car was new. It was considered OK to rering without boring the cylinders if the taper or wear was .007 inch or less. There were special rings for cylinders worn more than that but I doubt they make them anymore.

An advantage of today's rings is they are low tension and don't put much pressure on the cylinder walls. This reduces friction, freeing up a couple of horsepower and improving mileage a bit, while reducing wear to practically nothing. On engines built since the early 80s with low tension rings, when you take them apart there is practically no cylinder wear even at 100000 miles plus.

Get the valves ground at the same time and the valve guides checked for wear. If they are slightly worn they can be knurled back to size, if badly worn they must be replaced. Valve stem seals can be installed at this time if necessary. Not sure if they are recommended on a flathead Packard but some of the smart guys may have the answer.

quote:
" So in the beginning it smoked a lot but now not so much."

It will most likely clear up even more. Probably needs a good hard drive for 100 miles at a sustained 50 to 60 mph.

Do a compression test. If compression is no less than 75% of specification compression them i wouldn't ring it yet. Drive it out. Give that a try first.