This might be one of the greatest debates of all time. Everybody with an interest in classic cars has an opinion on the subject. I love that we are all so passionate about this, but let’s try to remember it all comes from a good place. We love our Mustangs, and we want the best for them, right? So, without hesitation I would like to throw in my two cents worth. What oil are you using in your classic? I use Brad Penn Oil 10W-30 Partial Synthetic Racing Oil in my 289 and it has never run so well, I believe this is why.
Let’s talk about oil for a minute before we get into the nitty gritty. What is oil and what does it do? Sometimes it helps to understand things before making big decisions. Oil is to your car what blood is to your body. It functions not just as a lubricant but also cools the hottest components in your engine by transferring heat. It must keep moving throughout your engine to continue working properly. Just like blood flowing through your veins distributing oxygen. It keeps metal parts from fusing together. That is why pressure becomes so important to keep the lubrication flowing.
Once it has been circulated through your engine for a few thousand miles it becomes dirty and contaminated from combustion byproducts and it loses its additives to heat and pressure. Therefore, it must be changed. Unfortunately, your car does not have a liver to clean it. Lubrication is the number one job of oil and we cannot let that break down, the barrier it creates between our engines moving parts is essential to its proper function. Now modern engines function a little differently than the classic ones we all cherish. This is where the debate usually starts. Should I use synthetic or non-synthetic? What do I do? Here’s my thought process.
When our vintage cars ruled the road, the oil that was available contained something called ZINC. This additive has all but been eliminated from standard oils readily available today. Why is this important? According to an article published in Mustang Monthy, “Oil companies started adding ZDDP (zinc dialkyldithiophosphate) to engine oil back in the 1950s to help reduce wear and tear during engine start-up. How important is ZDDP to your classic Mustang’s engine? It reduces bearing and journal wear by a factor of 20.” That’s a big factor, so if I’m looking for oil, I want to find one that closely resembles what was originally intended to be used in my car. Most engine wear occurs during start up, and if you have a dry engine, that can cause major damage. The majority if not all of the oil is out the engine when you start it, but Zinc remained and acted as an anti-wear barrier.
Unfortunately, this all changed with the introduction of the catalytic converter. Most cars built after 1975 had catalytic converters. According to the EPA, Zinc can damage these converters giving them a short life span. Therefore, it was decided that Zinc should be eliminated from oil.
After researching and trying different type of oils I stumbled onto Brad Penn. It is known as the original green oil and contains higher levels of zinc phosphates that are no longer available in standard oil. I have had my 1966 Mustang GT Coupe for almost 20 years and switched to this stuff last year. My engine has never sounded so good!
Without zinc in the oil, wear for vintage engines with flat tappet cams increases exponentially. According to Brad Penn, “The multi-viscosity grade and synthetic components facilitate cold starting and quicker engine warm-up while insuring adequate engine protection during competition. Brad Penn Grade 1 motor oil is desirable for their anti-wear additives, making them highly suitable for flat tappet camshaft engines. These high-quality race lubricants are 100 percent made in the USA for racers, engine builders, and enthusiasts. Brad Penn Grade 1 motor oils have unique base oil that causes them to cling to your engine’s parts, minimizing wear during high-torque, high-stress competition.” So I’m getting the benefit of higher Zinc levels to protect me on startup and shut down as well as partially synthetic enhancements as well. That’s sounds great to me.
So, in conclusion, my oil pressure remains high and temperature remains normal. There once was a slight tap in my engine that is now gone, and it sounds strong and healthy. There may be other brands out there and different theory’s but for me and my Mustang, I’m sticking with this green stuff. I would love to hear your thoughts and experiences, especially if you have tried Brad Penn Partially synthetic racing oil too. It’s not easy being green.