Shell Gas with Nitrogen Enrichment

OH! Maybe that's it! I noticed a significant MPG loss about a month ago and couldn't overcome it. I finally changed my tire pressures from 40/38 PSI to 45/43 PSI. I regained a couple of MPG almost bringing me back to previous FE. I only burn Shell. I thought it may have been a summer reformulation of the gas. So, what's the change they made and their rationale?

 

My last tank was disappointingly low. This included a trip to NY & short hop commuting in the summer heat. I'll have to buy gas within the next two days and expect a very high tank. Normal commuting & cooler than average temps. I suspect only a marketing effect.

 

You know, maybe this will rock the boat here, but I have actually noticed a 2 mpg positive difference so far. I have used Shell for 25 years, just because the station is down the street, and I have the gas rebate card I can stick in a pump, pump, and run!!!
Normally I have a large hill I have to drive up and down every day I go to work. I usually get 400 miles for 8 gal. of gas. This last tank, I am at 420 and just getting to the 2 pip mark, which is the spot I choose to refill every time.
My routine does not vary, same mileage every day, same hill, up and down. The only variable here is me, maybe I am having a rather good Hypermileing month, but what ever the case I am getting better mileage!

Go figure.
On a positive note...♦
I do like the Shell Card gas rebate!!!

 

My Prius also burns Shell (Regular) solely since day 1, its MPG is only creeping up by my improving of Hybrid driving-skills. But it's started out above 50+mpg at the beginning anyway.

 

Nitrogen is an inert gas. It does not burn, it won't help anything else burn. Why would anyone want it in gasoline?

 

According to a Shell press release....[FONT=arial, helvetica, sans-serif]

[/FONT]Shell has introduced Nitrogen Enriched Gasoline in all three grades. The new formulations contain a novel cleaning system designed to clean up gunky build-up on intake valves and fuel injectors.
Gunk (carbon deposit) formation on injectors can reduce fuel flow and fuel economy. Gunk has a porous surface that can trap the gasoline that is sprayed by the fuel injector; as a result, the fuel charge does not get in the cylinder at the right time, thus negatively affecting combustion.
Shell says that its Nitrogen Enriched Cleaning System contains a “carrier fluid” that acts like water, washing away both the cleaning agents and the engine gunk into the cylinder, where gunk is destroyed as part of the combustion process. In addition, The Nitrogen Enriched Cleaning System acts like a barrier to keep engines clean and protect them from performance-robbing gunk better than before.
Nitrogen is a key element of the active cleaning molecule in the new fuel, making it significantly more stable at the higher temperatures common in modern engines, such as direct fuel-injection gasoline engines. The increased stability ensures that the molecule can work under much tougher engine conditions by resisting thermal breakdown better than conventional cleaning additives.
Shell worked with automotive manufacturers to gain insight into current and future engine technologies. Nitrogen Enriched Gasolines were tested in laboratories, independent testing facilities, and on the road, accumulating more than a half-million miles in various vehicles and engines—including conventional, turbo-charged, and direct fuel-injection gasoline engines, hybrids, newer vehicles with low mileage, and older vehicles with high mileage.
Shell dual-fuel testing. Click to enlarge. Shell scientists used dual fuel engines to conduct head-to-head comparisons with other lower-quality gasolines. In these tests, split engines simultaneously run on different types of gasoline in order to collect data under the exact same conditions. The results of these head-to-head comparisons showed that the Shell Nitrogen Enriched Gasolines are more effective than lower quality gasolines in protecting against the build-up of harmful engine gunk, according to Shell.
The Nitrogen Enriched formula prevents build-up of gunk more effectively than gasolines containing only the minimum amount of cleaning agents as required by the EPA. The new cleaning system is certified to meet the Top Tier Detergent Gasoline Standard—voluntary standards designated by leading automakers (Audi, BMW, GM, Honda, Toyota, Volkswagen) to try to raise the bar on fuel quality beyond minimum government criteria.
Shell V-Power premium gasoline provides maximum protection with the highest concentration of the Nitrogen Enriched cleaning system and more than five times the minimum amount of cleaning agents required by federal government standards.

[FONT=arial, helvetica, sans-serif] I just feel cleaner already,
Clean & Green.
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