Standard or Premium petrol for your ST?

[circatee]

Not sure if I specifically asked this question, on this forum previously. 

But, for your ST, as a daily driver, do you use Standard or Premium petrol?

 

Thanks all

[circatee]

Probably best for me to follow the manual, 91 or higher. And, 93 if looking to maximize the 335hp... 

[WWWPerfA_ZN0W]

for ecoboosts, 93 is highly recommended for those looking for power or those who mash the wawa pedal on a frequent basis.  more octane = more available timing advance.

 

the real gains come after you put on an aftermarket tune.  mostly because the factory tune runs pig rich to protect the engine, so the tuners can lean it out without detriment.  but also because transmission shifting behavior is improved, faster and crisper.

[Vanquished]

Premium only.

I have sams club so I'm paying 3.05 a gallon right now. Other gas stations in the area are charging 3.64. I pay for my sams membership in just a couple of fillups lol 

[ben senise]

add me to the 91 octane club. i didn't buy the ST to hobble it with low octane gas.

[Fingernip]

I run 93 only. I always have tons of stop and shop gas reward points so I generally only pay $35-40 per tank. 

[TT Steve]

I only have 91 where I live. I have to add a good octane booster to get close to 93 but it does certainly help. I am right now going to run an unleaded 108 race fuel with my 91. Should be equilvilant to around 98 to 100. Tune going in now and will test and data log.

[2FAST4U]

I use 91 octane when available because of the tune I put in... but I'm pretty much disappointed with the tune's results though... If I knew, I wouldn't have bought the tuner, it's not worth it.

Claude.

[TT Steve]

On 10/4/2021 at 12:10 PM, 2FAST4U said:

I use 91 octane when available because of the tune I put in... but I'm pretty much disappointed with the tune's results though... If I knew, I wouldn't have bought the tuner, it's not worth it.

Claude.

 

I will be honest too, the 91 octane tune is pointless in my opinion. I am not having a lot of luck with the 93+ tune either. Or maybe I expect too much?

 

Right now from my previous tests, this is what I have gotten with the Dragy:

 

Stock tune, 91 octane with octane booster, 80' F at night at the strip 5300' altitude, basic 20 min cool down - 14.37ET @ 95mph

91 tune, 91 octane with octane booster, 78' at night on a Mexico street 5800' altitude, basic 20 min cool down - 14.42ET @97mph

93+ tune 1st ver,  91 octane mixed around 60/40 with 108 race fuel, 60' at night on a Mexico street 5800' altitude, 30 min cool down w/ water spray of intercooler(ambient temp when run starts) - 14.06ET @99mph

93+ tune 2nd ver (2'), 91 oct mixed around 60/40 with 108 race fuel, 60' at night on a Mexico street 5800' altitude, 30 min cool down w/ water spray of intercooler(ambient temp when run starts) - 13.99ET @99.30mph

 

I am going to the strip tomorrow and will be running a stronger blend of 108. Should be more like race fuel 70/30 with pump plus it will be like mid 70s and sunny. The reason I want a higher ratio is because I had an odd run where KR knocked a ton of timing out which killed power a lot in the midrange. Same night same conditions, etc. Tuner thinks octane is probably not where I think it is. How did I get a good run then a bad run? Data logs showed conditions actually slightly better on the run where timing pulled, Something does not make sense. I need to really study the logs to see if I am missing something.

[niceonept]

Petrol?

Only Diesel goes in my Edge!

[Cerberus]

full disclosure mine is a sport, not an ST, but still a 2.7 Eco.

When i read my owners manual and it said it was perfectly ok to run 89 octane i was kind of blown away..

I mean 10:1 compression and 15(ish) pounds of boost..? on Regular?! 

So, I have been running mostlty regular, but TopTier regular from Costco and other good sources.

But about 2 weeks ago I said screw it and switch back to premium, before taking 2 extended road trips.

 

Now, I don't know if its the fuel cleaning up carbon deposits (the piston crowns were black with carbon) or the ECU remapping ignition timing to use the available octane, or the air temps cooling off, (or some combination of all three more likely)

but there feels like a lot more giddy-up when you mash the loud pedal, perceived by my highly calibrated butt dyno.. ?

[omar302]

9 hours ago, Cerberus said:

Now, I don't know if its the fuel cleaning up carbon deposits (the piston crowns were black with carbon) or the ECU remapping ignition timing to use the available octane, or the air temps cooling off, (or some combination of all three more likely)

but there feels like a lot more giddy-up when you mash the loud pedal, perceived by my highly calibrated butt dyno.. ?

 

You SHOULD feel a difference. The owner's manual also states "For best overall vehicle and engine performance, premium fuel with an octane rating of 91 or higher is recommended."

 

A lot of newer vehicles, Ford's EcoBoost engines included, are designed like that. They can work with regular fuel, but using Premium fuel would yield better performance. Ford also had started advertising their Horsepower & Torque number when using 93 Octane fuel.

[akirby]

6 hours ago, omar302 said:

 

You SHOULD feel a difference. The owner's manual also states "For best overall vehicle and engine performance, premium fuel with an octane rating of 91 or higher is recommended."

 

A lot of newer vehicles, Ford's EcoBoost engines included, are designed like that. They can work with regular fuel, but using Premium fuel would yield better performance. Ford also had started advertising their Horsepower & Torque number when using 93 Octane fuel.

All true but it depends a lot on how you drive.  My wife would never notice a difference.

[Cerberus]

8 hours ago, omar302 said:

 

You SHOULD feel a difference.

Yes, i am aware of this. 

FWIW I am a lapsed ASE Certified Master Tech.

(Never bothered recertifying after the first time because it never made me one dollar more)

The post was more of a comment as to the fact that it was an obvious and significant  difference, and commenting just for commenting's sake. 

[omar302]

14 hours ago, akirby said:

All true but it depends a lot on how you drive.  My wife would never notice a difference.

 

And only for those with butt dynos ?.

 

12 hours ago, Cerberus said:

Yes, i am aware of this. 

FWIW I am a lapsed ASE Certified Master Tech.

(Never bothered recertifying after the first time because it never made me one dollar more)

The post was more of a comment as to the fact that it was an obvious and significant  difference, and commenting just for commenting's sake. 

 

I then misunderstood your post.

[TT Steve]

I can tell you what gains in the qtr mile you may see from 86 octane to 91 octane. Here is what I saw with all things being pretty much equal as far as weather, DA, heat under the hood, etc. and completely stock "Not Tuned".

 

14.90ET @90.76mph - 86 octane - 1/2 to 3/4 full gas tank full of fuel

14.59ET @93.21mph  - 91 octane - 1/2 to 3/4 full gas tank full of fuel

14.48ET @94.27mph - 91 octane with VP Racing Octanium Octane booster - 1/2 to 3/4 full of fuel

14.37ET @95.13mph same as above but with a K&N replacement panel filter - 1/2 to 3/4 full of fuel

 

These are "Tuned" runs on higher octane and a blend with the K&N air filter above and conditions are better than above runs:

 

13.98ET @98.77mph - 108 racing unleaded fuel mixed with 91 pump at a 70/30 ratio respectively - 1/4 tank full of fuel

13.89ET @99.43mph -  E30 blend -- 108 racing unleaded mixed with E85 measured potency of E70 - 1/4 tank to 1/2 tank full of fuel

I am honestly not impressed by the tunes. This thing should be in the mid 13s or close.

 

 

 

 

[enigma-2]

On 6/4/2021 at 11:04 PM, circatee said:

Not sure if I specifically asked this question, on this forum previously. 

But, for your ST, as a daily driver, do you use Standard or Premium petrol?

 

Thanks all

There are dozens of YouTube videos discussing the comparison of regular vs. premium.

 

This video is about average, the test the same car in a major, Canadian testing  laboratory changing only the gas used.

 

As expected, the milage is the same (compensated by the PCM) and shows premium has slightly higher pollutants (slightly higher amount of unburnt hydrocarbons).

 

Premium really only makes sense in very hot, dry areas (desert where the air isn't very dense) or towing heavy loads. Otherwise it's just an extra $10 per fillup down the drain.

 

 

[ben senise]

my '16 Ti 3.5 and my '20 ST 2.7 ecoboost both use about a liter less per 100 km with 91 than 87. both have used about 11.5 l/100km with 87 and about 10.4 with 91 octane. i have switched many times and the results have been absolutely consistent switching back and forth over many tanks of gas. i'd love to try 94 just out of curiosity.

Now is it worth the extra cost? mathematically not since it's <10% gain for >10% cost but it isn't $10/tank since i get more km. the image above shows a difference of 13.5¢/liter but where i live the difference is 20¢ or more.

but higher octane allows the engine to advance the timing more and thus get more power. that is indisputable. getting more power from the same amount of gas means you use less gas to get the same work.

 

edit to add: just watched the video above. it is so wrong in so many ways. their reasoning behind the tests on the dyno are completely false and illogical and i can demonstrate that empirically. and the consumers on camera? of course they have no clue about physics. "it's better for the car" isn't a valid argument. stuff like this depresses me.

Edited November 1, 2021 by ben senise

[handfiler]

2 hours ago, ben senise said:

my '16 Ti 3.5 and my '20 ST 2.7 ecoboost both use about a liter less per 100 km with 91 than 87. both have used about 11.5 l/100km with 87 and about 10.4 with 91 octane. i have switched many times and the results have been absolutely consistent switching back and forth over many tanks of gas. i'd love to try 94 just out of curiosity.

Now is it worth the extra cost? mathematically not since it's <10% gain for >10% cost but it isn't $10/tank since i get more km. the image above shows a difference of 13.5¢/liter but where i live the difference is 20¢ or more.

but higher octane allows the engine to advance the timing more and thus get more power. that is indisputable. getting more power from the same amount of gas means you use less gas to get the same work.

 

edit to add: just watched the video above. it is so wrong in so many ways. their reasoning behind the tests on the dyno are completely false and illogical and i can demonstrate that empirically. and the consumers on camera? of course they have no clue about physics. "it's better for the car" isn't a valid argument. stuff like this depresses me.

 

May taxpayer dollars that go into financing the CBC depresses me.

Edited November 1, 2021 by handfiler

[enigma-2]

Ummm, I would have thought that the Canadian Car and Truck Institute Laboratory would have been ably to run a simple dynamic test. Especially when the their representative had 20 years experience. Can't trust anybody anymore. 

[enigma-2]

Scotty's opinion.

 

Consumer Reports

 

ChrisFix

 

Dyno testing by Shell oil company

(~4% higher cylinder pressure due to ignition timing). Graphs, explanations. 

 

Crypto (reg vs prem with tune)

 

Oh, oh, wife yelling. Gotta take the trash out. Enjoy the videos.

 

 

Edited November 2, 2021 by enigma-2

[Cerberus]

Ok, there's a fair amount or horse shit flying around here..

I have to say, I am dubious / surprised / impressed if true that any mass market production vehicle is performing ignition timing control on each cylinder separately, or even on alternate cylinder banks separately as suggested by the shell pressure test.

However, that is still not a great test. 

Pressure average is not the metric that should be used anyway, what you really want to know is peak cylinder pressure at a specific point (about 6° ATDC iirc)

 

Yes high octane fuel offers more opportunity for more power if utilized correctly. 

 

Full disclosure,  I could not watch the entire video in some cases because of the  annoying drivel factor.

And I get it, dumbing shit down for Joe and Jane Consumer is necessary to some degree when dealing with extremely complex subjects, but it's damned annoying to feel like you accidentally got put in a remideal kindergarten class..

[hd2000fxdl]

30 years ago I would have been using the higher octan fuel because I was more interested in getting the most out of what I was driving. Move forward to now and I'm driving for best MPG, I stick with 87 and the money savings. No issue with Spark knock or anything close to that so I'll stay with what I have been using. If I want to race around, I'll use another vehicle that's meant for that.