OK, I got my car out of storage, did a bunch of misc. work on it and finally got it started, 10 psi oil pressure at hot idle, but it climbs to about 41 under throttle load. Engine only has 200 miles on it and I really don't want to rebuild it again. Hopefully this is just due to my shitty sunpro oil pressure gauge (mechanical). If not is the damage already done? I'm keeping my fingers crossed for air in the gauge. My mechanic friend said to get some tool (I think he said it was oil/trans pressure standalone gauge or something) to check for sure. Where can I get one of these? Does it hook to the sending unit?

I'm keeping my fingers crossed for air in the gauge.

Ay this car drives me to drink...

 

What weight and type of oil do you use? If you use 5W30 change it to 10W40 or even 20W50 for the summer. If you change to synthetic your engine will hold better oil pressure when hot. I'll try using thicker old before spending money and time on anything else.

 

Those pressures are fine. 10 psi per 1000 RPM is more than enough.

 

Air in the gauge line won't matter for final pressure indication. The gauge doesn't care whether it is sensing the pressure of liquid or gas.

10 PSIG at hot idle is adequate, although one would expect more pressure on a rebuilt engine with the proper oil clearances and the correct viscosity oil. For stock design oil clearances, normal engine temperatures, and a stock pump and filter, 10W30 mineral oil should be adequate. 5W30 lacks suffucient base viscosity to maintain pressure when heated, unless the engine is designed with tighter oil clearances.

With only 200 miles on the engine since rebuild, I suggest using mineral oil instead of synthetic (PAO) until there is at least 500 miles, preferably a bit more. Since you just took the car out of storage, the oil should be changed unless that was done immediately prior to storage.

Also, avoid using any oil filters with orange paint on them.

 

If you broke in your engine properly, 200 miles is enough. If you used a flat tapper cam it should be broken in in the first 30 min of engine operation. The only other part that recuire brake in is the piston rings and for those you needed to do a few runs at full rpm to get them to seat properly, that's all.
So you should be able to run synthetic oil now. GM use Synthetic in new Vetts and they have 0 miles on them. Their engines where broke in on the dyno. A long time for brake in is an old school myth that is proven wrong.

 

so wait let me get this straight the engine has 0 miles but it has been run on a dyno.... to break it in... have you ever seen them break in a engine... on a dyno or not? they flog the crap outta them which is equal to babying it for 500 miles or so...

and who cares what oil GM uses in a LS (insert new buzz number here)

totally different animal