What kind of Oil do i use for...

[msbaugh]

I get 15-40 SI-4 diesel oil for work in 5 gallon buckets for $60! 1500+ ppm zinc and i use it in both my truck and challenger. Y'all won't be able to get that though, not many plants manufacture them anymore. If stick with Brad Penn if I were you

[stinger]

I was thinking of using the Valvoline VR1. But it only comes in 10-30W or 20-50W. I had 10-40W for the break-in. I guess 10-30W should be ok. What do you guys think?

like I said I run 10w30,have a melling HV pump and have 80 psi cold and 40 warm@ idle. what's the rule,10 psi per 1000 rpm?

[dodj]

So what does the zinc do for you?
Rod posted a chart that lists ppm. What ppm zinc is a good number?
Ive been using Penzoil 10w30 in my 440 since it was rebuilt about 20 years ago. Nothing radical, touch more cam than a 70 magnum. Don't notice any problems?
Or are we just talking break-in?

[bc3j]

Using Joe Gibbs HR-2 10W30 conventional oil. Got it from Summit Racing. So far so good. Motor is a stock N code 383.

[Katfish]

I've read the older oils (and what the older engines need) is 1600ppm zinc.
The newer oils only have 1/2 that because of catalytic converters.
Even the diesel oils only have 1200pppm.

The Lucas additive is cheap insurance.

Zinc is an lubricant, newer roller cam engines don't need as much zinc.

http://blog.hemmings.com/index.php/2012/10/18/tech-101-zinc-in-oil-and-its-effects-on-older-engines/

[1970 RT Challenger 1970]

What I have used in the past with the ZDDP that you need:

15W50 Mobil 1 Synthetic

Castrol 5W50 Synthetic - (For Classic Vehicles on the label)

VR1 20W50 - Dinosaur Oil