91 Octane w/Arco or 87 Octane with Chevron and other "name brand" fuel?

here in oregon most gas is E10, there are 2 stations that sell 91 without ethanol, all my fuel is from costco, I will do more testing but at over 400 miles and that much differnce in mpg, something has changed. I started a new thred that should help gather info on 91 vs 87 in the prius c specifically.

 

Actually it is just the opposite, higher octane gasoline has lower energy content if ethanol is used as the octane boosting agent.

 

I would actually assume that they are not. Based on the link below, it would appear that to get top tier your additive manufacturer has to have their product independently tested to meet certain specs at a particular treatment level. The seller then has to sign an agreement saying that they will use that product at that treatment level and pay their annual fee. There is no indication that there is a follow up or inspection process to make sure you are doing what you say you are doing, but there may be such a process.

Top Tier Gasoline

Its also interesting that QT and Costco are now on the list.

Rob

 

I'll believe that when it snows a foot in Phoenix.

That was my point. It is mostly a marketing "strategy" ; much sound and furry signifying nothing concrete.

And we all know that those highly paid Corporate officers ALWAYS tell the absolute truth......don't we ??

 

It's interesting to watch the tanker , that just left one branded gas station , drop a load
Into another branded gas station , on the way to a different branded gas station ,,,,
Coincidence ??? I don't think so ...

 

...I agree that is interesting now we have Costco,QT, also BP is a new addition!

 

Yup, I agree. I've never put much stock in it, and buy gas at Arco which is the cheapest/busiest station in my neighborhood.

Rob

 

Diet only edge allowed.
Regular Gas and 40psi F & R tires.
60MPH limit!
50 miles on WGI short NASCAR Course
Priceless!

 

My lawn mower gets just as much CPF (clipping per foot) with Arco as any other brand. Never had a problem starting it either.

 

www.chevronwithtechron.com/products/documents/69083_MotorGas_Tech_Review.pdf

Here's a 124 page technical review of gasoline by Chevron.

• They say no benefit for Chevron Premium over Chevron Regular: as they infer both have the same amount of Techron.
• They do say suggest some brands are inferior due to not enough detergents
• Quite some discussion about energy content variations (MPG variations) in Premium vs. Regular. According to Chevron Premium averages 1% more energy content, but consumers should not use Premium for this reason because it will not pay off. In RFG areas Premium does not have more energy due to EPA RFG recipe. I still think some stations might have more than 1% energy content variations, believe they say it could be up to 8% variation, but that is based on old data. IMHO this is a very awkward discussion because the recommendation to consumers is basically to ignor that there might be some energy content variations.

 

High octane fuel is for higher compression, high performance engines. Back in the 70's when gas went to all unleaded, I had to run the higher octane in my chevelle just to keep it from knocking. Using it in today's engines that don't call for it is a complete waste of money. Go cheap, if it doesn't knock or ping, it's all good.

No one knows who's fuel is in whose pumps. Back during the oil crisis of the 70's congress passed a law saying any tanker could fill any station on their route. This was to save transportation costs. The law is still on the books. Gas is gas. All of it has all sorts of improved additives so buying the "next best super booster" additive at the local chain auto parts store is also redundant and a money waste.

 

In my personal experiance some of my cars get better mpg with different gas and some don't care what gas. all these cars are suposed to use 87 or better. Same story with ethanol some cars seem to loose mpg with ethanol and some don't. So IMO blanket statements like, "in todays engines its a complete waste of money" are inaccurate.

I have always heard that 91 was a waste of money in prius. I have a prius c and filled up with 91 and saw a 7 mpg gain. that is about 14% with an added cost of 6% and the engine seemed to warm up quicker and run smoother. I was suprised so I am checking into the idea of running 91 instead of 87 both fuels are E10, that is what we get in Oregon. I think that 87 is all you need for the engine to work properly, that doesn't mean it won't work better with 91.

 

I guess what i meant was, with today's technology, over doing with an engine designed for 87 octane with a slower burn 91 could have been a bit misrepresentative. Who knows, with an Atkinson cycle maybe there is a gain. All I know is that if I can get 40 on the highway with my 08 corolla why would I buy a smart car that requires a more expensive 91 octane to get 45? I'm still new to this with my Prius and I may have been comparing apples to oranges with engine design. Please keep us updated on your results and if it works out, I assure you, I'll switch to 91. Didn't mean to offend. The rules I went by when I worked on cars years ago may have changed with these things.

 

I will be amazed if A-B-A testing supports his claim, but I confess the Gen 2 engine underwent changes to become the c engine.

 

Its no problem. I think people on prius chat are really working to get the best out of their cars. It seems that almost everyone on prius chat if they have an opinion it is that 91 doesen't improve mpg and if it does its not enough to be cost effective. that is why I was suprised by my results on one tank of 91. I am now back on 87 and my mpg seems a little lower, even with the warmer temps. time will make it easier to understand how the different E10 fuels affect my mpg with the prius c. I will be going back and fourth with the fuels at least into summer.

 

I use only Shell 87 gasoline, have less than 1000 total miles on my 2014 prius 2, and on a city only and a highway only fillup. So far I'm seeing low 50s on both. I just aired my tires up to 42/40 from 38/36.