I have an LS7 427ci LS engine that came out of a wrecked, low mileage 2008 Corvette that is now in my ’69 Camaro Pro Touring car. We will soon have the car running and will be running the Camaro in some Pro Touring events and track days. The question came up of what motor oil to use for this engine. I’ve looked into synthetics versus semi-synthetics and I also ran across Driven’s different engine oils.
The LS30 High Performance Motor Oil looks to be something really good but the question is what makes it so much better that it costs roughly twice as much to change the oil?D.H.
This is a very interesting question that forced us to dig a little deeper than normal to come up with the answers. The descriptions that follow can get a little technical. We think that’s cool—but we geek out on stuff like this.
The Driven LS30 oil is a pure synthetic and offers what could be considered among the best additive packages for any purpose-built engine oil. Driven Racing originally blended this synthetic as a competition-oriented lubricant that would be operated at elevated oil temperatures and pushed well beyond the limits of conventional oil. But then they decided to offer this high performance oil for its more high-end street LS engine customers.
When choosing engine oil, the first requirement that you should consider is the viscosity. In the application where you will be using the LS7, the factory oil viscosity recommended by General Motors is a 5w30. Specifically, GM used a Mobil 1 synthetic oil. So a synthetic 5w30 would be a wise choice to continue to use for your engine. Since the application has changed to a non-emissions controlled car, you could now opt for a performance synthetic oil.
Understanding Synthetics, PAO & mPAO
Synthetics are a good choice for this situation because the base oil will be of a much higher quality. There are several different types of synthetic oil on the market so the term really has very few specific limitations on what defines the term. Within the synthetic base oils, there are Group III, PAO, and mPAO variants. According to Driven Racing, the LS30 uses the highest quality synthetic base which is an mPAO.
You may have heard of synthetic oil referred to as a PAO. This is an abbreviation for a polyalfaolefin which is a synthetically-derived base oil with a very stable chain of carbon molecules that provide engine protection through a very wide range of temperatures. For years up until roughly 2010, these PAO oils were among the best that were available. But in 2010 the lubrication companies formulated an even better synthetic base stock called mettallocene PAO (mPAO) that offers substantially improved temperature stability and performance.
This is currently the best base stock available but it is generally used only in the highest quality race engine oils. This mPAO base stock was originally created for use in off-shore wind turbines where high temperature and high shear (HTHS) oil stability was paramount because an oil change at sea is a ridiculously more expensive proposition compared to changing your oil in your driveway.
But now this superior performance mPAO base oil is available for your engine.
Base stock for most engine oils represents roughly 70 percent of the liquid with the remaining 30 percent as additives. This makes the base stock very important. The viscosity index (V.I.) rating is a SAE test that assigns a number for the base oil’s ability to maintain a given viscosity at both 40 degrees C (104 degrees F) and 100 degrees C (212 degrees F). The higher an oil’s viscosity index, the better its performance across that wide temperature range.
One of the best things about synthetic engine oil is that it has a higher V.I. rating than conventional engine oil. Each base stock will have its own V.I. We’ve listed the generic viscosity indexes for conventional, PAO and mPAO oils below.
Viscosity Index for Different Base Oils
|Base Oil||Viscosity Index|
|Mettallocene PAO (mPAO)||< 200|
The Role of Engine Oil Additives
All of this technical material is related only to the base stock. Now we need to look at the other roughly 30 percent of the oil as the additive package. As you might have guessed, the XP and LS30 based oils use the highest quality additive packages and include items like a higher level of ZDDP for engine wear protection along with other additives that improve the base oil’s performance.
Of course, this oil then is not necessarily recommended for engines with catalytic converters since LS30 contains a higher concentration of ZDDP.
If your engine was still in a production Corvette with its full emission package, then engine oil with the standard American Petroleum Institute (API) “donut” is what would be a better choice. But these oils are limited in their ZDDP content in order to quality as an API-certified lubricant.
Nearly all multi-grade engine oils also use a percentage of polymers as part of the additive package for multi-grade engine oil like a 5W30. The “W” does not stand for “weight” as is commonly thought. Instead it indicates “Winter” which refers to the oil’s viscosity at cold temperatures. The lower the first number means it will flow more efficiently at very low ambient temperatures. So a 5w30 will flow better at low temperatures compared to a 10w30 or a 20w50.
Multi-grade oil offers the ability to flow well at low temperatures like SAE 5 for example, while still providing adequate protection at high temperatures like SAE 30. This occurs because of the addition of polymer viscosity index improvers. With a very high quality mPAO base stock, fewer polymers are needed because the base oil offers a very high V.I. to begin with. All of these factors work together to produce high quality oil that is far more stable at both ends of the temperature spectrum but especially at high operating temperatures.
But all this performance comes at a cost—which is one reason why the Driven LS30 is more expensive. Essentially it is among the best oil you can buy for your engine.
So all this comes down to whether you think your LS engine deserves the best oil on the market. That’s a question only you can answer.
Of course, there are other engine oils that do offer high performance engine protection with improved additive packages (like ZDDP) that are not fully synthetic like Driven’s GP-1. This is also a high quality, lubricant that is based on a conventional, Pennsylvania-based crude oil. The GP-1 is only a synthetic blend, using a small percentage of Group III base stock. It is also much less expensive compared to LS30.
So now you have some additional facts to help you decide which oil is best for your hot rod LS7.