For the initial startup on a rebuilt engine I would use a non synthetic break-in oil of 10w30 weight even if you have a roller cam, its to seat the rings properly as well.
Drain the oil after the break-in period, I know it cost a few bucks but I'm sure that new motor cost a pretty penny.
After that a 10w40 should be good.
On my flat tappet annual oil changes..... after I've drained the oil with the drain plug still open, I pour a quart of inexpensive oil right through til drained then close things up, new filter filled with as much oil as I can, screw on then fill crankcase to capacity.
The extra zinc & phosphorous probably doesn't hurt the engine. I've been using Brad Penn with no problems for years. I also add a little of this once in a while, good additive.
https://lucasoil.com/products/engine...e-tb-zinc-plus

lol Basically what I am figuring out here is discussing oil is like discussing religion and politics. Everyone has a different opinion and thought. Seems like the majority of everyone seems to say 10W-40. I was leaning very strongly towards the Valvoline VR1 because of the Zinc additives in it. It doesnt get much colder than 30 degress here in Dallas and that is only for a few hours a night with average temps int he day around 50-60. However, in the summer it can get hot as hell. Temps around 100 or more and that may be rough on the engine.

Brad Penn Oils are now known as Penn Grade

Much like religion and politics, oil discussions digress because nobody has any hard data.

Eexcept I just posted the hard data. We have it. All you have to do is read it and it'll answer your question on what brand to buy - Any of them. Sure, oil A and oil B might do differently running down a board at 15 degrees F, or oil C and oil D exhibit different wear patterns when you lean a bar against a spinning steel wheel. Oil E and F might behave differently when put in a frying pan and heated beyond what they'd ever see in an actual engine. Those make for great marketing.

But where it matters - how much wear an engine undergoes during an oil change interval - the available evidence indicates there's really no difference. People that track the car and put the oil through stupid high temps probably need a good synthetic. Just about nobody else does.

The moral really is: Buy what you want. Even the cheap stuff is "good enough."

The other moral is: You don't need to pick among a pile of opinions. You can figure it out yourself and actually KNOW. Put 10w40 in the engine, warm it up, and check the pressures. Then put 10w30 and check again. You could do the testing back to back with the cheapest no-label mineral oil Wal-Mart carries for $40. As long as it has an SAE seal on it, the viscosity is going to be in the proper range regardless if it's $20 a quart Motul or $2 a quart generic brand.

Then you'll know exactly what weight to buy when you fill it back up with whatever brand you want to run. And by know, I mean you'll KNOW. It won't be speculation or presumption or rule of thumb. You'll know. Actual Truth.

Here’s a very informative read, that breaks down oil protection for you. Interestingly enough, most of the “break in” oils everybody likes to pay top dollar for, does a very poor job of protecting anything. Give it a read. Find out where your oil ranks. This is hard data, and data is your friend...

https://540ratblog.wordpress.com/

Ooops:

"201. “ZDDPlus” added to Royal Purple 20W50, API SN, synthetic = 63,595 psi
zinc = 2436 ppm (up 1848 ppm)
phos = 2053 ppm (up 1356 ppm)
moly = 2 ppm (up 2 ppm)
The amount of ZDDPlus added to the oil, was the exact amount the manufacturer called for on the bottle. And the resulting psi value here was 24% LOWER than this oil had BEFORE the ZDDPlus was added to it. Most major Oil Companies say to NEVER add anything to their oils, because adding anything will upset the carefully balanced additive package, and ruin the oil’s chemical composition. And that is precisely what we see here. Adding ZDDPlus SIGNIFICANTLY REDUCED this oil’s wear prevention capability. Just the opposite of what was promised."

I run Rotella T6 15w40 year round. Also a very good source of oil info with no BS and lots of facts is at https://www.bobistheoilguy.com/

I have emailed him before and he is very receptive to questions. Great read!

I use Joe Gibbs BR30 oil for break in and change it within 2hrs/50 miles plus the filter... then I switch over to Valvoline VR1 40W mineral oil (non synthetic) change at 500 miles.... then change every 2K miles.... I beat on my cars with lots of track days.... plus run e85 which does put some moisture into the engine. After 2K miles I run a synthetic oil.... Mobil1, Royal Purple, Amsoil.... whatever is cheapest among these 3. Always WIX filters.

:king: