87 octane vs 93 octane

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

rjdelp7

2000 XLT
Joined
Nov 30, 2014
Posts
1,529
Reaction score
378
Location
NY
Sea
I usually fill up at a Costco here in Mesa, AZ and the todays price was $1.58 regular and $1.88 Premium or 30 cents per gallon difference. Mine is only a 5.4L 3V but since I dropped a new ReMan engine, I thought I would up grade the gas to clean out the old injectors and I ran a bottle of Sea Foam through the tank as well. Really does run better on Premium and I have to admit that 30 cents a gallon or about $7.50 for a full tank is worth it to me. I like the performance.
Seafoam adds alcohol to the fuel. Not Good! Its for small engines.
 

Mike Wolfe

Full Access Members
Joined
Jul 9, 2017
Posts
479
Reaction score
174
Location
Tonopah AZ
I usually fill up at a Costco here in Mesa, AZ and the todays price was $1.58 regular and $1.88 Premium or 30 cents per gallon difference. Mine is only a 5.4L 3V but since I dropped a new ReMan engine, I thought I would up grade the gas to clean out the old injectors and I ran a bottle of Sea Foam through the tank as well. Really does run better on Premium and I have to admit that 30 cents a gallon or about $7.50 for a full tank is worth it to me. I like the performance.

Good morning
I live out in Tonopah, AZ
Prices out in my area run about $2.999 for regular & $3.399 for 91 octane premium
I think your prices for fuel must be in error
Are you sure it wasn't $2.88 for gasoline
 

sjwelds

Full Access Members
Joined
Feb 19, 2016
Posts
838
Reaction score
383
Location
Kansas
Filled up yesterday and the station was out of regular 87 so they were selling premium 91 at regular 87 price. WOOT!
 

Habbibie

Is it Christmas yet?
Joined
Feb 2, 2016
Posts
1,852
Reaction score
563
Location
Chicago
So the last 6 fill ups have been 93 octane on my 3.5L EcoBoost van, here's what I noticed:

No noticeable difference in driveability unless towing, without a trailer it feels and accelerates the same, but with a 6500 lbs trailer it hauls ass off the line. Down side to that is the brakes cant keep up causing them to fade rapidly.

Also my MPG's dropped significantly, I went from 14.3 average (I calculate the milage manually) to 11.5

Finally the motor doesn't scream as loud at the top of the rev line like it did with 87 empty (no trailer)

Conclusion: I'm going back to 87 on next fill up, sadly the extra power while towing doesnt offset the mpg difference & even with having a WillowWood big brake kit it still proves too much for them reaching operating speed before slowing down again in city traffic vs with 87 I'm usually at half that speed by the next traffic light, the quietness of the motor is nice but I tend to keep it under 4k rpms so I always have boost anyways.

Maybe it'll act differently with the expedition/F150 crowd but my 2nd gen EcoBoost has showed me what it can & can't do with 93 octane in a 1,250 mile endurance test.
 

1955moose

Full Access Members
Joined
Nov 23, 2014
Posts
6,004
Reaction score
1,351
Octane boosters are hard on fuel systems, as well as the motor. No unfortunately you got to pay it forward if you want that extra oomph. Before Ww2, rumors had it that scientists and engineers couldn't come up with the formulas for extra octane needed to run high compression overhead valve engines. Before 1949 when the first Ohv Oldsmobiles, and Cadillacs started hitting the showrooms, compression ratios were low. 7.0 to 1 or lower was the norm out of Flathead Ford's, Packard's, Buicks, etc. The chemists seemed to hit their stride around 1946 or so, rumor has it. In the following 15 years or so, big Pontiacs, Ford's, and Chevy's, were putting out 11 to 12.1 compression ratios. I remember up untill around 1979 here in the Bay area, we had gas stations that were selling 102 octane fuel. Up till 1973 gas was .35 cents a gallon for premium. Who cared if your big block Mustang only got 7 mpg!

Sent from my N9131 using Tapatalk
 

mquick5

Full Access Members
Joined
Aug 27, 2018
Posts
589
Reaction score
154
Location
Buckeye Country
I wouldn't mind a big block mustang in today's gas prices even if it got 1 mpg!
If you do happen to get that bb stang I know where you can get some 100 octane for a mere $7.50 a gallon! Picture from earlier this year, so probably about $6.75 a gallon now.

5b2119658ec253e017d167219cbca684.jpg

Sent from my SAMSUNG-SM-G870A using Tapatalk
 

1955moose

Full Access Members
Joined
Nov 23, 2014
Posts
6,004
Reaction score
1,351
Are you in Arizona? We don't have any retail pumps with octane that high. I think the racetrack still has as we used to call it hi test fuel. $7.50 x 30 gallons for our sleds. $225.00 per fill up. Habbibie those Mach 1 429 big blocks are out there. About $100 grand will park one in your garage. My fav was the 71 in yellow.

Sent from my N9131 using Tapatalk
 

Habbibie

Is it Christmas yet?
Joined
Feb 2, 2016
Posts
1,852
Reaction score
563
Location
Chicago
Haha that's why I wouldn't mind one, a good investment on what seems like an appreciating piece of history.
 

mquick5

Full Access Members
Joined
Aug 27, 2018
Posts
589
Reaction score
154
Location
Buckeye Country
Are you in Arizona? We don't have any retail pumps with octane that high.

Sent from my N9131 using Tapatalk


I'm in Ohio, this station is in Lancaster. There are several stations that sale the race fuel but, usually closer to the drag strips.
 

1955moose

Full Access Members
Joined
Nov 23, 2014
Posts
6,004
Reaction score
1,351
I couldn't find buckeye county, except Arizona. What's ironic is your in an area that still uses [emoji470]/buggy. The Amish. Maybe deep down those 1850 mindset individuals want to rip ass down the road in their new Dodge Challenger hellcat! 100 octane is definitely better than hay for that kind of horsepower!

Sent from my N9131 using Tapatalk
 

1955moose

Full Access Members
Joined
Nov 23, 2014
Posts
6,004
Reaction score
1,351
Sorry, I thought when I read Lancaster, you were in Pennsylvania, like our old departed friend Bedrck 47. Lancaster Ohio, different location, but still good to know, you can buy go fast juice there.

Sent from my N9131 using Tapatalk
 

aggiegrad05

Full Access Members
Joined
Nov 6, 2017
Posts
1,834
Reaction score
1,392
Location
North Texas
Dumb question from someone clueless: what happens if you put the 100 octane in an Expi?

Is it like putting premium in a Saturn (it’ll run just fine and you’re wasting your money) or is it bad for the engine?

I’m not planning on doing so (I don’t like ******* away money and I don’t have access to the stuff anyway) I’m just curious.
 

rjdelp7

2000 XLT
Joined
Nov 30, 2014
Posts
1,529
Reaction score
378
Location
NY
Dumb question from someone clueless: what happens if you put the 100 octane in an Expi?

Is it like putting premium in a Saturn (it’ll run just fine and you’re wasting your money) or is it bad for the engine?

I’m not planning on doing so (I don’t like ******* away money and I don’t have access to the stuff anyway) I’m just curious.
I have used 100 octaneAVLL(aviation low lead), in my 79 KZ650 Kawasaki and 03 FXD HD. There are leaded and unleaded products. High octane is a bit harder to start, cold. In a normal vehicle will run fine on unleaded 100. I believe VP C3, contains lead. It produces a strong, chemical smelling exhaust, that racers love. In my motorcycles, they ran the same, until I hit the throttle. Under hard acceleration, there is a much better, smoother and powerful response. The engine does runs a bit hotter. 100 octane was first used during WWII. It gave piston aircraft engine an advantage. Most of the 100AV gas was refined in that era, from Texas crude.
 

mquick5

Full Access Members
Joined
Aug 27, 2018
Posts
589
Reaction score
154
Location
Buckeye Country
As far as I know in a regular vehicle it may not even run! If it does run, it will be poorly. You have to have at least 12 to 1 compression to take advantage of the race fuel. Some say 110 Octane won't even ignite with a match but under high compression it's a whole nother story! Higher octane fuel produces less detonation.

Sent from my garage using Tapatalk
 

aggiegrad05

Full Access Members
Joined
Nov 6, 2017
Posts
1,834
Reaction score
1,392
Location
North Texas
As far as I know in a regular vehicle it may not even run! If it does run, it will be poorly. You have to have at least 12 to 1 compression to take advantage of the race fuel. Some say 110 Octane won't even ignite with a match but under high compression it's a whole nother story! Higher octane fuel produces less detonation.

Sent from my garage using Tapatalk

I have used 100 octaneAVLL(aviation low lead), in my 79 KZ650 Kawasaki and 03 FXD HD. There are leaded and unleaded products. High octane is a bit harder to start, cold. In a normal vehicle will run fine on unleaded 100. I believe VP C3, contains lead. It produces a strong, chemical smelling exhaust, that racers love. In my motorcycles, they ran the same, until I hit the throttle. Under hard acceleration, there is a much better, smoother and powerful response. The engine does runs a bit hotter. 100 octane was first used during WWII. It gave piston aircraft engine an advantage. Most of the 100AV gas was refined in that era, from Texas crude.

Thanks!
 

RealmGirl1

New Member
Joined
Dec 12, 2023
Posts
3
Reaction score
0
Location
Maryland
I've tried changing over to higher octane in my recently purchases 2018 XLT and now my engine light is on.
 

Attachments

  • Screenshot_2023-12-12-10-48-18-79_f85a9dcae275ee1e0920d804e6924647.jpg
    Screenshot_2023-12-12-10-48-18-79_f85a9dcae275ee1e0920d804e6924647.jpg
    45.1 KB · Views: 9

Left Coast Geek

Full Access Members
Joined
Aug 31, 2023
Posts
634
Reaction score
312
Location
Mid Left Coast
I've tried changing over to higher octane in my recently purchases 2018 XLT and now my engine light is on.

its only the Platinum with the factory 400HP tune that requires 93. The regular 375HP tune on the XL, XLT, Limited should work fine on 87.

You need a full feature ODBC reader (I use ForScan Lite on my phone with a bluetooth ODBC dongle) this will read *ALL* the codes from all the modules. basic ODBC readers will just read smog related codes.
 

jjscsix

Full Access Members
Joined
Jul 22, 2023
Posts
273
Reaction score
119
Location
texas
The Platinum does not “require” 93. This from the 2023 manual

IMG_1482.png
 

Attachments

  • IMG_1482.png
    IMG_1482.png
    436.4 KB · Views: 5
Last edited:
Top