When Shell began advertising nitrogen enhanced fuel, I was skeptical. It’s not as if we’re short of nitrogen on our combustion chambers because nitrogen makes up roughly 78 percent by volume of the air that we breathe.
Because of the way nitrogen be-haves in the combustion chamber, automakers spend plenty of money making sure the nitrogen that comes out the tail pipe is not harmful to us.
I managed to track down two Shell guys who know nitrogen.
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Alex Drohomyrechy is a product quality adviser for Shell Canada and Bobby Bowden works for Shell Global Solutions.
Canada has minimum standards for fuel quality. Standards deal with items such as cleaning agents and emulsifiers to keep the different components of gasoline from settling out, plus octane stabilizers and more.
While the Shell fuel at your local station may not have come from a Shell refinery, it still must meet Shell’s standards. The first time a non Shell fuel goes into a Shell truck, an additive package is put into the fuel to bring it up to Shell standards.
On some gasoline components, the Shell standard is up to five times higher than the government’s minimum.
As for the nitrogen, the secret is now out. It’s always been there.
Secret molecular design
The part of the additive package responsible for keeping deposits from forming on the face or stem of the valve has been developed in the lab. The technically engineered, modified nitrogen molecule now falls into the synthetic category and has become proprietary information that Shell won’t talk about.
This new molecule has some desirable traits. It’s soluble in gasoline at all temperatures. It dissolves existing carbon deposits on intake valves and it prevents the formation of new carbon deposits.
The only impact noticed on exhaust valves was that once the intake was clean, the exhaust valve tended to clean up too. But, there is no scientific proof of significant improvement.
Drohomyrechy and Bowden said there are a couple of points that need to be emphasized.
First, if an engine is badly carboned up, changing to Shell fuels could cause the existing carbon on the valve to come away in chunks, which could cause engine damage.
The second point is that switching to Shell fuels will not make a worn engine better. If the valve stem oil seals are leaking or the rings are weak, those conditions will not change.
You may operate with less carbon on the valve, but it will still use oil and lack power.
Seeing is believing. Shell has a regular V6 with two fuel systems. Each system runs a bank of three cylinders. One bank runs on Shell fuel while the other runs on a discount fuel.
The discount fuel did not come from some swamp-soaked set of pumps in Louisiana, but from a reputable discount dealer in Montreal.
The test lasted for 5,000 kilometres.
When a scope was sent down the intake of each bank, the lack of carbon on the Shell side was incredible.
I have also discovered that some auto manufacturers have had carbon buildup issues, including Toyota, BMW and GM. To resolve the problem, they recommended Shell fuels.
Switching fuels could be an inexpensive way to remove carbon buildup. It has to be cheaper than blowing crushed walnut shells down the intake ports, as BMW did under warranty to their cars that didn’t perform as expected.
The big question is this: does your vehicle get better fuel economy on Shell with this newly engineered nitrogen additive?
Both Bowden and Drohomyrechy waffled on this point and would only commit to the general statement that the operating efficiency of the engine improves noticeably.
They also admitted that other fuels in Canada may meet the same standards as Shell fuels, but Shell is the only company committed to a uniform standard at every station.
This all comes down to the old adage of “if it isn’t broken, don’t fix it.”
In other words, if you’re happy with your fuel, stay with it.
If you’re not happy, try Shell.