I'm planning on pulling out the engine/trans in my '66 Chrysler 300 here pretty soon and am looking for ideas on how best to freshen it up. It's a stock 4bbl 383/727 and 100% street driven. On kind of a tight budget here - thinking about just doing a basic overhaul, maybe a new cam. Any suggestions?
I hear there is a problem with the cylinder head valve seats?

you're right. the valve seats on what you have will not be hardened and were used with ol' skool leaded pump gas. todays unleaded gas will wreak them.

100,000 miles maybe. I have never had a problem with unhardened seats in a stock engine. But I've only been at this for 45 years or so. Not that hard seats are a bad thing and if you are having a the heads redone go ahead and have them installed .

if your on a real budget just put some new main, rod, cam bearings in it, hone the cylinders, put some new rings on the pistons. a new timing chain, lap the valves, maybe this cam and lifter set from summit-

http://www.summitracing.com/parts/SUM-K6400/

w/ valve springs to match
new gaskets and valve seals which are usually included in the gasket set.

probably around $500 if you do all the work you possibly can. maybe 4X that amount if you pay someone to do it.

My '64Dog has maybe 113,000 miles on its original non-hardened valve seats and no sign of valve recession. And I'd know it if my valve lash started closing up.
That's with stock cam and valve springs. In general Mopars don't have a lot of valve seat issues if you're using a mild cam and springs. Put a fast-acting cam in it with big springs and I bet it'd be different.

In the SAE tests on valve recession the number one cause of recession was, IIRC, time at wide open throttle. So you could probably cruise from Maine to California and back repeatedly if you didn't spend too much time at WOT.

If you're having work done on the heads new seats are nice, though. Check out the prices. Your heads will work a lot better with the larger stock size 1.74" exhaust valves and a few hours spent in the bowls and ports with a die grinder. Then a 2 1/2" exhaust system with H-pipe, a performance curve in the distributor, get the jetting right in the carb, and you'll notice an improvement.
I'd choose a really small cam with 110 degree LSA.

R.

The car was my daily driver for about a year in '08, then was in storage while I was overseas, until yesterday. My intention is to switch between this car and my '82 Gran Fury for daily driver purposes. I do notice a light ticking noise (like a sewing machine) on the passenger side top end - figure it's old lifters?

What type of oil should I be using in this engine? It's all stock and has about 120K miles on it.

The ticking noise - yes, probably a lifter.

As for oil, I'd use either a High Mileage oil or a HDEO (diesel oil). Use 10W30, 10W40, or 15W40 depending on your oil pressure and climate.

Would the Amsoil Z-Rod 10W-30 be a good choice for this engine?

When I pulled the 516's off of my 383, to port them, the valve seats were severely sunk and beat down. My motor was running the MP 933 valvespring, 484 cam, at the time. They have something like 300+ lbs pressure at around .500 lift IIRC. Dunno any history on it, was used and abused prior to me.

We can only guess until you tear into yours and find out.

Pay the $$ and get hardened seats and upgrade to 1.74's as mentioned.

Otherwise a hone and re-ring + freshen the valveguides. The valveseats will get beat about pretty good when the guides are sloppy.

First of all, about any oil would be okay for the engine. Your cam is already broken in and if it is stock cam stock springs there is nothing to worry about. You probably have less than 100 lb seat pressure, probably closer to 85 lb, and a valve lift of 0.425 or less. If and when you change cams and springs, it would be more important.
It's not fashionable to say that, but it's the truth. If there was a real problem with old stock engines it would have come out by now.
NOTE:
I was in WalMart the other day and ran across a new product, High Zinc motor oil, rated SL, not SM or SN. It may have been Valvoline. It's not expensive and would be what I'd suggest for a stock daily driver. If it was a high dollar engine with big cam and springs I'd go Joe Gibbs Driven oil. But you don't need to spend that amount.

If the lifter is ticking it is probably because of varnish and I'd suggest running Diesel engine oil for a month or so, because the Diesel oil has really high detergent levels which might clean it up. But the high detergency makes it harder for the zinc compound to work. So for the long run, a gasoline engine motor oil is probably better.

R.