I've wondered how much different oils affect power, economy?
I dumped the factory-fill 5w30 oil out of my 6.o Liter Chevy and put in 5w30 Full synthetic at 1,300 km.
I could swear it has a little more power. And the economy computer says its getting 2-3 MPG better on the highway with the syn oil. Always use regular grade Co-Op gas in my work trucks.

The new shell gas is supposed to clean out any carbon deposits in an engine.
I can see this new N2-enriched gas really being a benefit to our RoadStar engines, I bet it will work just dandy...
Anytime you can get rid of depsits and reduce your "frictional horsepower" losses in your engine you gain some power and economy.

GM claims that factory-filling their differentials with 75w90 Synthetic (as opposed to 80w90 Dino)
will gain 0.5 miles per gallon better gas mileage in a pickup truck. Especially in cold climates like we have here.