The best oil by far would have to be Mobil 1 MX4T, but at $8.50Qt that is a lot of $. It also has just about the strongest addtive package you can get, unless you mail order your oil.
MX4T plus a tank of leaded gas made me think I had a new engine under the hood of my Z28. I see why they got rid of strong addtive packages and leaded gas, engines would never ware out.
For the money I have gone with 5w-40 Shell Rotella T Synthetic. $16 per gallon it is cheaper then mobil 1 in the 5Qt.
It has the "SJ" and "SL" gasoline rating, so even the 3800 guys can use it.
Also there is no chance of sluge build up.
I was looking at the addtive packages over on bobistheoilguy.com and the new mobil 1 oil rated "SM" has gained real weak addtive package.
Mobil 1 was the better out of all the SM oils.
SM is weak to the point where your flat tappet cam and lifters will grind each other into dust. In this case new is not better.
Shell Rotella T gained the CI-4plus for the new 2007 diesels, that makes it a little bit weaker diesel engine oil but that makes it the perfect oil for older gasoline engines.
If your like me and don't have a roller cam (2.8, 3.1 or 3.4 camaro engines, older 5.0 and 5.7) you do not want to use "SM" oil. 99% of every thing is going to be "SM" rated unless it is Diesel engine oil or 4 stroke motor cycle oil.
I bought about a dozen cases of Mobil 1 15w-50 and 10w-30 in 2000, It is all "SH/SJ" rated. It is about to run out. So I had to find some thing new.
Lets just say in 2000 I had never though about puting heavy duty diesel engine oil in my car, if I had known I would have loaded up on Rotella and not mobil 1.

 

check out the amsoil. it has the additives you are looking for. performanceoiltechnology.com

 

Not to get off topic but can one person tell me how bad it is on your motor to run leaded gas such as CAM 2? I seen he said he put it in his car?

 

Leaded gas is great for your engine.
It is very bad for your catalydic converter.
After a few minutes of running 100LL your conveter would be dead.
It will also kill your oxygen sensors, but not as fast as you might think.
The lead will also foul your plugs sooner.
I do not have oxygen sensors or a converter so leaded gas only makes my car run better.

 

if you want to run your standard oil you can also but some engine break in additive from the gm dealer that is around 6-8 bucks. i install some in all engines i build now. have not had one camshaft failure since. i put a new extreme camshaft (small 252 advertised duration) and used mobil one after using the newer oil (i didn't know yet) and the lifters are bad after 500 miles. replaced the cam again and used the gm additive with the same oil and no problems, swapped to amsoil after break in

 

Their is the Crane Cams "Cam break in lube".
It has so much ZDDP that black stone labs can't even get a straight reading form there oil sample burn machines.
I want to get a bottle of it and just use an ounce per oil change.
I just compleated installing new connecting rod and Main bearings on my diesel. I used GM's E.O.S. assembly lube for every thing even priming the oil pump.
It is like gear oil but with out the stink.
It says in the back lable not to use it as an oil addtive.