What kind of oil is best for turbo Cars?
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Why have engines changed?
automakers have been turning to technology
You might start to wonder, “What’s wrong with the good old engines we’ve all used for years?”
The answer has to do with CAFE requirements.
Since the 1970s, the government has made it so that each automaker’s fleet of vehicles has to get a certain average amount of gas mileage or face fines.
The minimum allowed fuel economy has steadily gone up over the years, and after the Trump administration recently rolled back some Obama-era plans, it is now set to reach about 40 mpg by 2026.
Turbocharger 101
So, how does a turbo improve fuel economy?
Let’s look at how they work to find out.
Basically, a turbo is an air compressor that is powered by the exhaust gases. The gasses turn a turbine, which pulls air through the intake and forces it into the combustion chamber.
This improves combustion by adding more oxygen, which shows up as more horsepower and better gas mileage.
We drivers think turbos sound great. Less fuel, more power. What’s going wrong?
The heat is on
So, how does a turbo improve fuel economy?
Let’s look at how they work to find out.
So, a turbo can go faster than 300,000 rpm.
Just think about that for a moment. To put this in perspective, the top speed of the average car today is around 6,000 rpm. This means that the turbo can spin up to 50 times faster than your engine.
The gases that turn the turbine can also be hotter than 1,000°F (538°C). When there is a lot of speed and a lot of heat, deposits can build up. This is called “turbo coking,” and it can ruin the turbo.
What’s the best oil for turbo cars?
Since engine oil lubricates and cools the turbo, it makes sense to use the best oil you can find in your turbocharged car or truck.
Using a high-quality synthetic oil like AMSOIL Signature Series Synthetic Motor Oil keeps performance up and keeps deposits from building up on the turbo spindles.
In fact, it protects turbos 72% better than GM’s dexos1 Gen 2 specification says is needed, as shown here.
Another tip is to let your turbo car idle for a minute or two after driving.
The oil will keep the turbo cool and stop deposits from forming that hurt its performance.
Let’s be direct
Automakers have also become more interested in gasoline direct injection (GDI). In fact, almost every company makes use of this technology in some way.
In a traditional port-fuel-injected engine, the fuel injectors are in the intake manifold. In a GDI engine, the fuel injectors are in the combustion chamber.
By doing this, automakers can control the timing of fuel injections very precisely and, in some cases, do more than one injection during the same piston stroke.
Because the computer has such precise control, it can change the ratio of air to fuel to as lean as 50:1 in certain situations. In contrast, port-fuel-injected engines run at about 14.7:1.
This precision results in improved fuel economy.
Pump up the jams
GDI engines also have a high-pressure fuel pump that can generate up to 2,000 psi of fuel pressure.
In comparison, port-fuel-injected engines run on fuel pressure around 40 psi.
Increasing the fuel pressure helps to cool the cylinder and spread the fuel out more evenly so that it burns better.
Fuel dilution in GDI engines
Again, GDI sounds like nothing but upside for us drivers, but there are drawbacks.
With the injectors located in the combustion chamber, over-spray can hit the far cylinder wall, allowing fuel to wash past the rings and into the oil sump, contaminating the oil.
Automakers are constantly changing piston designs to trap fuel in the combustion chamber, improving efficiency and reducing fuel dilution.
Intake-valve deposits in GDI engines
Another downside are intake-valve deposits.
In a port-fuel-injected engine, the intake valves stay clean because detergent-rich fuel flows over them.
But in a GDI engine, fuel doesn’t touch the back of the valves anymore, which causes deposits to build up.
Over time, these deposits can make it hard for the valves to close properly, which hurts performance and gas mileage.
Use the best oil and additives in your turbo and direct-injected car.
Most of the time, neither your turbo nor your fuel injectors will give you trouble as long as you keep up with regular maintenance and use high-quality motor oil and an oil filter, like AMSOIL synthetic motor oil.
It’s also a good idea to use a strong fuel additive like AMSOIL P.i. to clean and keep the injectors working well.
Use AMSOIL Upper Cylinder Lubricant all the time to keep the gains made with AMSOIL P.i. It gives the engine more lubrication, which helps it keep more horsepower and use less gas.
Be wary of low-speed pre-ignition
But when these technologies are used together, it can lead to low-speed pre-ignition, which is an abnormal combustion event that could be very dangerous (LSPI).
LSPI is turning the lubrication industry on its head. To fight LSPI, oil companies have to change the way they make motor oils so that automakers can get the most out of the fuel-saving benefits of T-GDI engines.
We’re proud to say that the engine test for the GM dexos1 Gen 2 specification showed that AMSOIL synthetic motor oils gave 100 percent protection against LSPI.
I’ll leave you with one last thought: embrace the changes that modern engines have made and enjoy the better performance and gas mileage they bring.
And you can rest easy knowing that AMSOIL synthetic lubricants provide the next-level protection that modern engines need to work well.
Why AMSOIL? Superior protection against wear, improved fuel economy and better performance under extreme temperatures. AMSOIL is the only oil that is able to last up to 25,000 miles. Save yourself time and money and protect your car or truck by using AMSOIL products. Your vehicle will last longer and you will lower your maintenance expenses. Protect your Honda, Toyota, Nissan, Chevrolet, Ford, Chrysler or any other vehicle with AMSOIL synthetic oil!
We advise you to consult your owners manual for proper fluid recommendations and to consult the appropriate repair manual for proper maintenance procedures and specs. Follow all appropriate safety practices. We are not responsible for misuse of products.