Shell V-Power test

[Rick Rae]

Originally Posted by 1993CivicVX

you get some consistent gas mileage. It even starts to drop off evenly as the weather gets cooler. although maybe you don't live in a seasonal area.

Well, these numbers are averaged over thousands of miles. If you take a look at my gaslog you'll see it jumps around pretty good.

Yes, Virginia is seasonal. I'd say average temperatures have dropped maybe 20F across the period of the test. Do you think that's what we're seeing in the numbers?

I plan to loop around again (maybe several times) in the hopes consistent trends will emerge.

Originally Posted by VetteOwner

do your shell pumps have 10% ethonal in them too? cuz that 10% ethonal could be causing slightly less mpg cuz of the ethonal

I don't know. I've read that the ethanol mix is government mandated but it's like CAFE in that it's across all blends, and that Shell doesn't add it to the higher grades. I have no idea if that's true. It was one of my theories for the higher numbers on V-Power originally, though.

I've also been told that ethanol is involved with the Winter formula down here, and some places just don't bother to take the stickers off come warmer weather; again, I don't know for sure. I did see one sticker that said the gas "may contain up to 10% ethanol," which is just the sort of wording one might use for seasonal stuff.

I guess ethanol, ECU self-optimizing to consistent gas, lubricating additives... the actual reason wouldn't really matter (though it would be nice to know). If running on one particular brand is less expensive or gives one better mileage, that's the important bit.

Originally Posted by Telco

Excellent, another person proves that different fuel stations can show different MPG.

It's a little early to say this proves anything, I think. I need to get through the second "A" segment first to see if I return to baseline (or what the new baseline is). Then, what with changing temperatures, Winter gas, refined driving techniques, etc, loop through the whole test again (or a few times) to look for repeatable trends. Anything else could be explained away as noise.

Also, remember the original intent was to see if the V-Power detergent claim held up. It wasn't until I got into it that the consistent gas/higher-quality gas factor started being discussed. So I didn't really come into the test gathering all the information I maybe should have to test that.

As for cheapest gas per mile versus per gallon, if it looks like Shell gives me consistently better mileage I can do some data-gathering on that. With gas prices fluctuating as much as they do lately, I'd need to gather prices from both Shell and the cheapest generic stations I normally use at each fill. That'd get closer to a fair comparison than using fill costs alone. Example: Prices here are up about 10 cents a gallon right now from when I was in the middle of the Shell portion, so if I calculated based on fill prices, Shell would have an unfair advantage.

If you ever have to rebuild the engine...

I don't know whether to hope I never have to rebuild the engine, or that the car lasts me so well for so long I eventually need to.

The test continues; stay tuned...

Rick