Summit Racing oil

Racing oils come in many grades. There is zero reason to use a 20w50 grade oil in anything that is naturally aspirated unless the engine builder used clearance from the 1970’s. And that’s crazy.

Oils are some much better today than they were even 15 years ago it’s surprising so many people still think in 1970’s era oils.

And even though it may not appear as such, oils are changing rapidly. It’s hard to keep up with it. Just because the grade and the name on the bottle is the same what you buy today probably isn’t exactly what it was 3 years ago.

If you buy an oil based on its zinc content you will most likely buy the wrong oil. More zinc isn’t any better than less zinc.

The formula of the blend is more important than what one chemical is.

Zinc is a power killing additive. It has a purpose and is a necessary evil in engine oils. Like I said, more isnt better. Especially if someone is adding it to an oil. Some Tribologist spent big money and time developing the oil. Anything you add to it will affect the whole chemical make up of the oil and it will most likely be a bad thing.

Fortunately these engines will take much more abuse than most people think. So screwing up with an oil choice usually doesn’t have immediate effects on longevity.

I would sit down and call 6 or 10 oil manufacturers and ask them about what oil you need. Take notes. And then make a decision. The cheaper oils aren’t usually the best.

As an example, let’s say you have brand A oil. They build a nice 5w30 (they say). When you look at the numbers you can see that the oil is built on the low side of the grade. We are not looking at the 5 winter grade side of the oil. We are looking at the 30 grade.

Being that it’s built on the low side of the grade, as the temperature goes up (viscosity is temperature based, the hotter the oil the less viscous it is and there is no such thing as oil “weight”) the oil can and probably will drop out of the 30 grade and now be in the 20 grade. I suppose that’s ok IF you understand what that means. Or maybe it’s a bad thing. If you really need the 30 grade and this oil falls to a 20 if the temperature gets high enough then you have an issue.

In that case, you may want to use a 40 grade oil in that brand so when the temperature gets up it may fall out of the 40 grade but it will be a 30 grade oil.

On the other hand, you may find a certain brand of oil that is built on the high side of the grade. So you can use the 30 grade and it will stay a 30.

Or, maybe you can drop down to a 20 grade as long as it’s built on the high side and will stay a 20.

Just as an FYI, the grade that an oil fits is pretty wide. And an oil is only required to pass the test a percentage of the time. Say 6 of 10 times it’s tested.

Again, that’s why cheap oils are cheap. Cheap components. Skating by on the grade. Things like that.