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As stated in subject line I did a compression on my 38 8 cyl today. The results were quite perplexing. I got about 60 psi in all but #4 which was 30 psi. Oil in the cyl didn't seem to change anything except good old #4 (brought it up to 60). Isn't 60 psi a bit low? Am I due for a ring and valve job?

Before an interpretation, how about a few details. Did you do it with all the spark plugs removed, throttle and choke plates held open, and crank for at least 3 compression cycles to a maximum reading? If not, you should should repeat the test before any interpretation.

yes to all of the above

Low compression readings could be the result of valve lash adjusted too tite.

Has the car been running recently????? When was the last overhaul???? How many miles are on the engine??? WHAT prompted u to do a compression check in the first place????
How well does the engine start and run????

I drive the car quite often. I do have a slight shake at idle and it does seem that I should have a bit more power but otherwise the car drives fine. Now that I installed an OD tranny I can cruise at 55-60 at about 2400 RPM. I was just doing routine checking of things in general. I had it out for a 150 mile trip Sat. and all was fine. Maybe I'm just too used to driving a 300 HP 2800lb car as my daily driver.

If oil consumption is reasonable, I'd suggest that a valve job is probably in order, assuming the tappet clearances are now reasonable. Assuming the guides are OK (they're a dog to change!!) it's a pretty easy job, though not a quick one. Valves if needed, often just exhausts, are readily available.

If the seats are reasonable and still narrow with no battering or other flaws and the valves OK, simple lapping could do a very nice job. If not you'll want to reface the seats and possibily have the valve faces machine-surfaced. You don't want to hand-lap the fit of a freshly machined valve and seat, it can't be improved on. Here's the power seat refacing equipment I use, it's an old Black and Decker with a Sioux diamond stone facer. I just finished a valve job on a 38 Eight (120) and would be glad to give any advice you might need if you tackle it yourself.

EDIT: If you're going to power-grind the seats, best to get someone who has the equipment and has done it before to help. And don't forget the inlet seats and exhaust seats are ground to two different angles (30 and 45 degrees). If you've not done it before, GO SLOW and get advice along the way. For example, if the seats become wider than about 3/32 inch due to refacing, you'll want to use stones of both narrower and wider angles to narrow the seat and center it on the valve face - take patience and care.

I've done more valve grinds on flathead Packards that I can count, feel free to phone or PM me if you want more advice.

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I still would like to know what psi is reasonable for a 282.

Depends a bit on whether Std or HC head, and if and how much the head might have been milled in the past, but 95 psi is a reasonable minimum expectation, factory spec is 110 psi for the standard head (82.25 - 86.25 cc volume) and 118 psi for the HC head (74.5 - 78.5 cc volume), volumes measured with the spark plug in place.

Do you have a shop manual for your car - all this info is in it.

Good thought Gusha, and it's a possibility but symptoms aren't all there, at least based on what we've read. Normal symptoms for a head gasket failure are 1) coolant loss, (2) overheating, (3) steam from the tailpipe on startup, (4) perhaps water in the oil, and (5) 2 adjacent cylinders with very low compression. Also the engine performance would be noticeably rough, sputtering at the tail pipe, and lousy power.

And let's not forget these engines in their prime typically required valve grinds every 25,000 - 40,000 miles.

How much trouble is it to pull the oil pan on this particular car????? if he has to pull the head to grind the valves why not pull the pan too and install a set of new rings????? Chances are if the valves need grinding then it probably needs new rings too.