Thread: *Oil For 1971 350 sbc*

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I have a 350 sbc with double hump heads, aluminum high rise with Demon 625 carb, nice cam, Sanderson headers connected to flow masters. I'm running Brad Penn SAE 20W-50 Partial Synthetic high performance oil in. This is what the previous own was running. I can not get the oil locally. What other oil would be a good substitute?

What gas do you run?

Originally Posted by robot

What gas do you run?

High octane pump gas.

My recommendation is to NOT use the high $$ oil....since it is a street driven vehicle, a good quality
oil is sufficient....oil changes are probably more important than the type of oil. If you like synthetic,
Mobil 1 is the gold standard. If you don't want synthetic, the major brands are probably all good,
people all have their favorites but choose one and stick with it... The "racing" oils are a great
profit producer for the manufacturers. I personally like brand X but don't like brand Y or brand Z.
You can fill in the blanks for the brand names.

You don't mention the vintage of your engine, but by saying "double hump heads" it makes me consider that the previous owner was using the Brad Penn oil because it's a flat tappet engine. There are different opinions on the subject, but back in the early '90's the OEM's were seeing that catalytic converters were being blinded by phosphorus, and to some degree by zinc which was coming from oil burned during the combustion process. In '96 the oil companies limited phosphorus to 0.10% by weight, and then in 2004 dropped it to 0.08% where it remains today. By that time most of the OEM's had changed, or were changing to roller cams so it was OK for them, but the instances of flat tappet cam failure in existing, older engines increased dramatically. A performance engine builder that I respect highly wrote an article for a periodical published for rebuilders, and stated that it was not a question of "if" a flat tappet cam would fail, it was a question of "when", if not running oil with the old levels of ZDDP, formulated by the oil company. IMO the ZDDP additives are not a good option, because it's been proven by testing that too much zinc and phosphorus will start building up on high load surfaces, also leading to premature failure, other than for breaking in a new engine.
The previous owner told you he was running Brad Penn's oil, and the advice to pick your oil and run it forever is pretty good advice, IMO. Why tempt fate by changing, especially if you're running an old style flat tappet cam?

Thanks for the info guys.