I have a '90 740 turbo with 253000 original miles. The engine is strong and fairly quiet but uses about a quart of Mobil1 every 200 to 500 miles. I know the turbo probably is using some of that. No obvious signs of smoke except a puff on heavy acceleration sometimes. The cylinders all compression test to 112 psi with almost no variance between cylinders (less than 2psi). My thoughts are to re-ring with Deves rings, replace the piston rod and journal bearings and main bearings/seals along with oil pump spring. Should I have the cylinders bored up to the next piston size as a general rule or can I just re-ring the engine after a good hone?
Thanks!

We have 231,000 on our '90 744 Turbo, and it is also starting to run low on compression. It only uses about a quart in 1500 miles, so I'll wait.

However, our car has pretty decent piston slap, does yours? If so, I concur with the suggestion of waiting for measurements to help you make your decision.

I would try to find out what standards for fit were used when they made our engines. Tighter might be a problem.
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3 8s & 2 7s 740,000 miles total

dang only 112psi, i just check the compression on my 89 N/A W/ 250000 and i pulled 160+ from all pistons, sounds deff like you have some rings ready to go.

My experience is that you won't be able to determine that until you are able to get a micrometer into the bores and check for wear.

Randy