2aroundtheworld
Active Member
There is also a sticker on the tank that says the same (at least on my 2012). I use whatever I can find.
I have a 2023 Super Tenere, the owner's manual says 91 octane fuel?
- Thread starter Campion
- Start date
Quisp
New Member
Octane has nothing to do with carbon build up. Just use a top tier fuel.
www.bellperformance.com
.
Using Premium Fuel In Your Vehicle
Wondering if you should be using premium fuel in your vehicle? Read on to find out...
www.bellperformance.com
As everybody knows, gasoline manufacturers have claimed this and that over the years. Each claiming to be the best. I don't know if they're all the same or not. But I was driving a 5.7L Dodge and using Shell regular. Was getting up 14s MPG. Began using Shell premium that claimed to clean you motor back to new. Within 2-3 tanks, I could feel a performance improvement; octane. But still was getting mid 14s mpg. After about a year and a half, and 10k miles, I was getting mid 18s, almost 19. Same type of driving. Don't have the car anymore, but it made me a believer and am still using the premium in the Tenere, but regular in the Jeep.
So yeah, octane is for performance, and detergent is for carbon build up. But I do believe that premium has more detergent(s) than regular. At least Shell says theirs does.
So yeah, octane is for performance, and detergent is for carbon build up. But I do believe that premium has more detergent(s) than regular. At least Shell says theirs does.
WJBertrand
Ventura Highway
Agreed, this was true years ago because fuel makers saved their best detergent additive packages for their premium grades. The impression that this is still true is a widely held misunderstandingOctane has nothing to do with carbon build up. Just use a top tier fuel.
.Using Premium Fuel In Your Vehicle
Wondering if you should be using premium fuel in your vehicle? Read on to find out...
Later, when fuel injection replaced carburetors, even in economy cars, the lack of adequate detergents in regular fuels caused issues with FI cars. There was a bit of tussle between car manufactures, forced to adopt EFI to meet emissions and mileage requirements, and fuel makers that were reluctantly playing catch-up. Since the late 80s, pretty much all major name brand fuel grades include better detergent packages.
Sent from my iPhone using Tapatalk Pro
Octane is to retard ignition so you can advance timing / compression. It is NOT for performance. In fact, using higher octane (91) in a vehicle designed for lower octane (say 87) will not give you as big a 'bang'.
The 5.7 MOPAR recommends 91 octane. The manual says that lower octanes can be used, but the performance will be degraded. The higher the compression, the higher the required octane. Never seen a low compression performance motor.
As Jeckyll says, by delaying the ignition, you can reduce the autoignition (due to excess temperature in the combustion chamber)….the hemi 5.7 has two knock sensors (one per bank)…when they detect a knock, it corrects the ignition and so on manages to cool the combustion chamber…. delay the ignition, implies a decrease in performance
WJBertrand
Ventura Highway
Because with premium fuel the engine computer will advance the ignition timing farther. As long as you avoid knock, advanced timing tends to improve performance.
In order for this to be true the engine must be equipped with knock sensors and variable advance.
For an engine designed to run on regular that does not have a knock management system (i.e. has fixed ignition timing), using premium has no advantage over regular.
Sent from my iPhone using Tapatalk Pro
A couple of summers ago, I was puting premium in my Jeep; recommends 87. But it was sitting for weeks, sometimes a month or two. It's gets driven once a week now, so it's back on an 87 diet. Still gonna use the 91 in the bike due to our heat and the additives. I also forgot my wife's new MX5 calls for premium.
If you talk to guys who tune turbo cars, they need to understand this well (or things go 'boom')
I have programs for both 91 and 93 octane for my car, same peak boost (twice stock) but different power delivery, fuel mapping and ignition timing.
I have programs for both 91 and 93 octane for my car, same peak boost (twice stock) but different power delivery, fuel mapping and ignition timing.
WJBertrand
Ventura Highway
Yup. The hot air is less dense so the EFI computer doesn’t need to add as much fuel to make the correct stoichiometric ratio. It’s a similar effect as riding at higher altitude.
Sent from my iPhone using Tapatalk Pro
Sent from my iPhone using Tapatalk Pro
When we went to AZ my 16mpg Jeep was getting 25mpg. But it didn't have 285hp anymore.
pvwheeler
Member
I dont know about down your way, but up here in Canada our Shell premium was ethanol free until last year. If thats the case it might account for a bit better mileage as well. I always found worse mileage with corn gas,back when we still had a choice. For a long time our Shell business supplier was selling us ethanol free regular as well. Now all we get is E10
Our pumps have one sticker for all three grades that say that the gas may contain up to 10% ethanol. I know that when I had to switch to E10, my mileage dropped by 2mpg in my truck. There is one station in town that claims it has ethanol free gas. The problem is driving through town, and it's not a Shell station.
Interesting thing about ethanol cars. The Hellcat/Demon 170 requires E85 and makes a gazzillion HP with it.
Last edited:
Ethanol has a higher octane number than gasoline, which allows you to raise the compression rate without causing detonations and if you add to that ethanol has "oxygen" in its composition... it is the ideal combo for power
Yes, apparently, the 107 in the name is for the octane rating.