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Proof premium fuel is better.

Clint Beastwood

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#42
Even without an e30 tune they can add 1.5 gallons of e85 per tank to to get their octane up to a full 93... I mean, even 91 tunes run like crap on their 91 gas from what I experienced, at least they can max out a stock tune properly this way, but again *if* e85 is available.
For sure - stratified 91 tune in the winter? Totally fine, no knock.
Same tune on 91 summer blend? LOTS OF KNOCK.
Add 1.5 gallons of e85? Good to go.
 


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#43
I hate to repeat myself but facts never go out of style

The more octane a fuel has the harder it is to combust. This means timing can be advanced closer to TDC thus making more power on the power stroke.
 


Capri to ST

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#44
I hate to repeat myself but facts never go out of style

The more octane a fuel has the harder it is to combust. This means timing can be advanced closer to TDC thus making more power on the power stroke.
I'm probably also repeating myself, but it just doesn't make sense to me to buy a performance car and then hamstring the performance with lower octane gas. I am in favor of letting the car realize its full performance potential.
The price difference between 87 octane and 93 here in North Carolina is about $0.60 a gallon. If I'm doing the math right, if you drive 10000 miles a year, the difference would be about $240. I believe you get a little bit better mileage on 93 octane, and this would further lower the price difference between the two grades of gas.
 


D1JL

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#45
I hate to repeat myself but facts never go out of style

The more octane a fuel has the harder it is to combust. This means timing can be advanced closer to TDC thus making more power on the power stroke.
I've heard this before. LOL
 


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#47
I drive in the city. I can't feel any difference between regular and premium (several comparisons). Is that because the stock tune limits power in 1st and 2nd gear? In the city I don't very often get to run it hard in 3rd or higher gears.
 


gtx3076

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#48
High compression+high boost=higher octane.

Look at the gains the 2018+ mustang gt's are making on ethanol. Ethanol didn't use to net much more than maybe 12hp on naturally aspirated cars, now they can take advantage of the higher octane thanks to the higher compression ratios.
 


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#49
I've just passed 1,300 miles on my '19 FiST and decided to use Shell 93 octane for three reasons:
1) Shell is top tier
2) 93 has much more of the additives than 87 to keep DI valves cleaner
3) I get $.30 off per gallon using the Shell Fuel Rewards and Giant Food points
I'm not much into any power increase of 93 over 87 so that argument is irrelevant to me. I've had vehicles with as little as 80hp and as much as 310 and their fun factor wasn't based on power.
 


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#50
I drive in the city. I can't feel any difference between regular and premium (several comparisons). Is that because the stock tune limits power in 1st and 2nd gear? In the city I don't very often get to run it hard in 3rd or higher gears.
I think that's a reasonable guess. If a full boost 87 octane costs 8.5-13hp, it might be even less in first in second gears. Alternatively, you simply may not notice it, there's not a huge difference.

magneticpersonality said:
2) 93 has much more of the additives than 87 to keep DI valves cleaner
...
I'm not much into any power increase of 93 over 87 so that argument is irrelevant to me. I've had vehicles with as little as 80hp and as much as 310 and their fun factor wasn't based on power.
Can you point to evidence of that (a greater quantity of additives specifically for cleaning valves)? Additionally, do we know if "more additives" is comprehensively better?

I agree with your point about power, cars can be fun for different attributes. My last car had 455hp and I don't miss it.
 


gtx3076

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#51
I think that's a reasonable guess. If a full boost 87 octane costs 8.5-13hp, it might be even less in first in second gears. Alternatively, you simply may not notice it, there's not a huge difference.



Can you point to evidence of that (a greater quantity of additives specifically for cleaning valves)? Additionally, do we know if "more additives" is comprehensively better?

I agree with your point about power, cars can be fun for different attributes. My last car had 455hp and I don't miss it.
I don't know how any valves are going to get "cleaned" since we our intake valves never see fuel, and our exhaust valves only see exhaust gas.
 


XR650R

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#52
I think that's a reasonable guess. If a full boost 87 octane costs 8.5-13hp, it might be even less in first in second gears. Alternatively, you simply may not notice it, there's not a huge difference.



Can you point to evidence of that (a greater quantity of additives specifically for cleaning valves)? Additionally, do we know if "more additives" is comprehensively better?

I agree with your point about power, cars can be fun for different attributes. My last car had 455hp and I don't miss it.
Not saying it's evidence, but Shell says it's better.
https://www.shell.us/motorist/shell...YK3LMdBPg3k6o1ebtcRoC-lAQAvD_BwE&gclsrc=aw.ds

I posted some vids on the 1st page. Post 16.
 


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#53
I don't know how any valves are going to get "cleaned" since we our intake valves never see fuel, and our exhaust valves only see exhaust gas.
"The test engine operated on a TOP TIER gasoline averaged 19 times fewer intake valve deposits than when it was operated on non- TOP TIER gasoline. (based on the ASTM D6201 test - TOP TIER gasoline averaged 34.1mg of deposits per intake valve versus non- TOP TIER average of 660.6mg)
...
In most cases, carbon deposits can be reduced or removed from critical engine components by switching to a gasoline that meets TOP TIER standards."

https://www.aaa.com/AAA/common/AAR/files/Fuel-Quality-Full-Report.pdf
 


gtx3076

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#54
"The test engine operated on a TOP TIER gasoline averaged 19 times fewer intake valve deposits than when it was operated on non- TOP TIER gasoline. (based on the ASTM D6201 test - TOP TIER gasoline averaged 34.1mg of deposits per intake valve versus non- TOP TIER average of 660.6mg)
...
In most cases, carbon deposits can be reduced or removed from critical engine components by switching to a gasoline that meets TOP TIER standards."

https://www.aaa.com/AAA/common/AAR/files/Fuel-Quality-Full-Report.pdf
Fuel never hits our intake valves unless people are adding aftermarket port injectors, so it's not relevant to most Fiesta ST owners.

View: https://youtu.be/LjJSbHxIvnM?t=99
 


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jmrtsus

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#55
The problem with marketing videos like this one is they tell you zero about the negatives.....like 7 times more cleaners in the fine print it is 7 times the fuel using the minimum concentration of cleaners required by the Feds to be a "top tier gas" and not compared to other name brand top tier gas concentrations. Or jumping on the nitrogen bandwagon....nothing new just new to Shell and some studies suggest it also increases NOX pollution. Corrosion test shown uses SALTWATER......how the hell do you get SALTWATER in your oil? So basically they match what other top tier gas companies do but promote a new ad campaign with Nitrogen enriched gas and Nitro power! Along with more pollution and no real help for our cars.....just more expensive. BTW, my MP215 has NEVER liked Shell or Chevron. Both give lower MPG than Sunoco or BP 93 Ethanol and much less that 93 Non ethanol by Marathon. On the other hand the Coyote likes Shell!

And next time my oil gets SALTWATER in it I'll look for some Shell gas to keep my valve stems from rusting.......not really, I bet all name brand gases use the same additives. Ahhhhhh......the magical "friction reducing molecule" in the fuel that they do not disclose....wanna bet it is PTFE? Any metallic friction reducing agents like titanium would not stay suspended in gas. Took Kendall many years to get it suspended in a thick oil and that was patented. If Shell had that it would be worldwide gasoline history. People should never take an ad as proof of anything other than marketing hype, but few will do any fact checking of these videos.
 


jmrtsus

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#56
"The test engine operated on a TOP TIER gasoline averaged 19 times fewer intake valve deposits than when it was operated on non- TOP TIER gasoline. (based on the ASTM D6201 test - TOP TIER gasoline averaged 34.1mg of deposits per intake valve versus non- TOP TIER average of 660.6mg)
...
In most cases, carbon deposits can be reduced or removed from critical engine components by switching to a gasoline that meets TOP TIER standards."

https://www.aaa.com/AAA/common/AAR/files/Fuel-Quality-Full-Report.pdf
If you drive an ST the gas never sees our valves........so is cannot clean them. Even so who would use a non top tier gas in our cars? "Quotes" are meaningless on this subject, the ASTM D6201 test does not use a gas direct injection (GDI) engine like ours.
 


gtx3076

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#57
If you drive an ST the gas never sees our valves........so is cannot clean them. Even so who would use a non top tier gas in our cars? "Quotes" are meaningless on this subject, the ASTM D6201 test does not use a gas direct injection (GDI) engine like ours.
Racetrac is not top tier, and I fuel up there almost exclusively on my ethanol tunes because it has the most E85 pumps around here. Ran that stuff for years on my last platform, and will do the same on this one.

I'll take 93 from racetrac over 87 from Shell.
 


PunkST

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#60
Im doing good with kwiktrip 91 in winter and citgo 93 in summer. Everywhere else their premuim is always stale and runs like more doo doo than it has been.
 


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