Gas Premium Octane

[jaherbst]

2 SPYD3R's, 990 & 1330, over 65,000 miles, sea level to 18,000 foot elevation, 87 Octane only, and never an issue..... :thumbup:
Dan P
SPYD3R F3-S

Now where did you find a road that was 18,000'. Really? I am giving you (2) Pinochios.

Jack

 

[spydermanstever]

Has anyone else noticed a similarity between Octane threads and Tire threads? No matter how many times they pop up, we still beat them like a dead horse. :bdh:

And recently, we can add the threads on the "drive belt tension" topic to that list too - lol - but hey, I think it makes for an interesting forum when members are willing to share their ideas and opinions on topics that, for lack of of better word, get "re-discussed" occasionally. I enjoy reading and contributing in this forum even in threads that will never have a period, like the "good morning" to all thread! :yes:hyea:

 

[rays hell]

Octane

Stale separated 93 or fresh 87 ?
You decide.

 

[BajaRon]

Stale separated 93 or fresh 87 ?
You decide.

Is this a rhetorical question?

 

[Dubliner]

"I asked a simple question, my manual shows 91 octane, and I asked can I use 93 octane. Only looking for yes or no. Thank you. "


Even with a "yes, or no" question; that still leaves room for at least two differing opinions... :shocked: :banghead:

Maybe? :yikes:

 

[unclegeezer]

My 2014 RT Limited runs fine on 89 or 87

 

[Wildrice]

Yes or No or Maybe

I asked a simple question, my manual shows 91 octane, and I asked can I use 93 octane. Only looking for yes or no. Thank you.

Maybe There is no free lunch--some thing paid for it. How the engine handles a lower octane fuel is by retarding the timing from it's highest advanced rating. Part of normal vehicle marketing is mpg. The more the timing is reduced from its peak level it also reduces the power and mpg---not significantly noticable. Thus if you saving money by buying the lower suggested rating fuel you are losing money via fewer mpg.
All riders are not the same---if you're a lead foot--buy the highest octane; if your a Sunday cruiser you probably could get away with the lower octane.
Some of the newer vehicles have "direct injection" kinda like a diesel (directly into the combustion chamber) which allows lower octain fuel to run just fine in a high compression engine as it reduces the time the fuel needs to be in the combustion cyl prior to ignition.. The bulk of the other engines "even if they print injected" are injected into the top of the intake maniford at the carb entrance--slightly more pecise than normal carburator--but basically the same. Maybe....
Getting a yes or no answer will be a rare occurance on this forum----I'm starting to enjoy it more than Facebook--reminds me of a local coffee shop with a regualr group of old timers debating the worlds direction & best course of action--gotta luv it

 

[Bob Denman]

Now where did you find a road that was 18,000'. Really? I am giving you (2) Pinochios.

Jack

:shocked: :agree: It pegged the needle!

 

[TXSHOTGUN]

Being in North Central Texas, I have run 87-93 octane in my 13 RT LTD, (AKA lovingly Flaming dragon/Can Ams shovel head), I get better performance out of the 87. I always add an ounce of Lucus oil Ethanol neutralizer and fuel stabilizer to each tank of fuel. 1oz per 5 gal. The higher octane seems to get worse fuel economy, maybe more ethanol added, thus more evaporation. Anywho, my 2 cents worth.

 

[jaherbst]

Flying Tigers...

There are two roads at or above 18,000. One in India and one in Bolivia. Who would of thunk it! However no Spyders have been reported there. Anyone?:shocked:

Jack

 

[Bob Denman]

The Death Road in Bolivia... :shocked:

 

[Wildrice]

high altitude and engine performance

There are two roads at or above 18,000. One in India and one in Bolivia. Who would of thunk it! However no Spyders have been reported there. Anyone?:shocked:

Jack

*I had 25' motorhome with a Ford 460 cu in engine & 4:11 rear end. Going through Eisenhower Tunnel in the Colorado Rockies at 12,000' I managed to hit 35 mph with foot on the floor in 2nd gear for over a mile+. I talked to another guy at a parking site & I asked him how well his 30' motorhome did towing a car up through the same tunnel. He said he just flew up through it with his Chevy 454 cu in power; I told him I couldn't get above 35 mph in 2nd gear; then he replied he was in 1st gear at 17mph.:banghead::banghead::shocked::shocked:
14,000 would be a stretch---16000--18000' highly unlikely..... Althought Kathmandu is waiting:yes:

 

[Wildrice]

In simple terms yes, there is no problem. Reading your signature line shows you run an Akrapovic pipe. Are you running the cat bypass also? If so, you may find the 93 will let the timing not retard and give you more bottom to mid performance.


In regards to reading these other posts, many have mentioned pre ignition. Octane is the fuels ability to have a controlled burn under pressure. If the fuel explodes rather than burns you have detonation, this is bad if not controlled. Pre ignition is different from detonation. Pre ignition is when something other than the spark plug begins the burning of the fuel. Often it is blamed on hot exhaust valve edges, carbon or a sharp cross section in the combustion chamber, even an improper spark plug heat range.

Depending upon various design factors, unless an engine has the ability to operate on higher octane efficiently, the higher octane can produce less power. However if the engine design can "tune" itself, additional performance may be gained.

We have always run 93 with Yamalube Fuel Med Rx in our 14 RTs. Stock pipe with a cat bypass.

PK

KEY DEFINITIONS
Detonation: Detonation is the spontaneous combustion of the end-gas (remaining fuel/air mixture) in the chamber. It always occurs after normal combustion is initiated by the spark plug. The initial combustion at the spark plug is followed by a normal combustion burn. For some reason, likely heat and pressure, the end gas in the chamber spontaneously combusts. The key point here is that detonation occurs after you have initiated the normal combustion with the spark plug.
Pre-ignition: Pre-ignition is defined as the ignition of the mixture prior to the spark plug firing. Anytime something causes the mixture in the chamber to ignite prior to the spark plug event it is classified as pre-ignition. The two are completely different and abnormal phenomenon.
Some detonation is fairly common in some engines & results with no failure problems
Pre-ignition aka knocking will cause damage to the engine...pps:pps::sour::sour::sour: