I have the choice in my area (South Carolina) of running 93 Octane premium (10% ethanol) or 90 Octane (No ethanol).
I have been running 90 ethanol free, and the engine seems good with it. I really don't like ethanol. Will the lower octane hurt?
Comments??
Thanks...Jimmy

PS...Merry Christmas!

 

If there is no detonation or ping as signs of pre ignition, it is fine.


Higher octane rating than the engine requires is a waste.


My LT1 does just fine on 87, 10% Ethanol as well!! 94 Jeep enjoys it as well....


Carl

 

Nice to see that even in the dead of winter all the myths and misinformation about gasoline, octane ratings, ethanol effects, top tier branding and brand x vs. brand y stuff gets dragged out for a good run!

 

Thanks...there has been no pinging. The manual calls for 93 Octane so no waste. I just don't want ethanol, seen what it can do to hoses etc. on older cars. It would be great if I could find 93 with no ethanol, but it doesn't seem to exist in this part of the country.

...Jimmy

 

That's surprising. Are you sure?

Nothing higher than 91 is available in most of North America.

 

93 (10% ethanol) is available just about everywhere. Most all stations have 93. I was on a road trip last week that took me through 6 states that all had 93. My wifes new car requires 93 octane (per manual). It's the no ethanol that is hard to find.
...Jimmy

 

I've never seen any car that requires 93. Jags from the late 90s onwards require 91 as per owners manual.

Maybe you can get 93, most of North America cannot. Unheard of in CA I think.

Ethanol is a separate unrelated issue.

 

No one has mentioned that high octane fuels are cleaner than low octane fuels , meaning less "gum" build up through the ENTIRE fuel system and less changing of fuel filters .If you are eco minded it also has less emissions and generally will give a slight improvement in fuel economy .IMO there is nothing wrong with E10 but the vehicle must state that it is suitable for E10 or as a member has already stated the fuel hoses will break down , another obvious solution is to change the fuel hoses to a type suitable for ethanol ,double check at the auto store.

 

That's because it's an old myth. Read the top tier website if you don't believe me.

All cars sold in North America since the late 80s/early 90s are E10 compatible. Certainly the OPs car is.

 

Ok...first of all the higher octane is used for higher compression engine to prevent detonation and other wise no different from lower octane fuel. Same cleaning etc.. Mickey is correct.

My wifes last car (a C300 Mercedes) called for 93. Her new car (Acura) requires 93 all per the manual.

According to Google, 93 is available just about everywhere, except the west coast.

Lastly...I screwed up, the 94 Jag V12 requires 95 RON by the Manual which relates to 91 Octane and means that the 90 (no ethanol) that I am using is cool.

THANKS....Jimmy

 

It appears that vehicles in your neck of the woods , came out much much earlier than in Australia . I will check the web site you mention , right now our government is considering banning all low octane fuels as a measure to improve emissions and protect the environment ( doesn't mean they are right!) on top of that , many car mechanics and some car organisations etc recommend using 98 octane in about 1 in 4/5 tank fills to clean the system if using " standard fuels " ie 91octane here in Australia . Our vehicles here have a sticker saying E10 suitable at the fuel cap. My imported 95 Camero has no" sticker " saying that it is safe to use Ethanol type fuels ! but I will check the OM .All in all it is getting harder to know what is right or wrong but for my jags 96/98 octane rating is all I would use . I suppose we could ask the oil companies , they wouldn't lie would they.

 

Chevron stations in BC have 94, as does Petro Canada in Alberta (some stations) and BC. I have no idea about provinces east of Alberta.

 

Not to be too pedantic- but which model? No Acura I know of requires 93 octane. Those that don't use 87 require 91.

 

Whew???


That octane thing again. My two cars do just fine on 87!!! 94 Jeep I6, well over 200 miles on the odo.


83 Jaguar wuzza 6, now powered by an LT1 sourced from a 94 Cadillac Fleetwood Brougham. Admired at the gas station yesterday, by a fellow car nut... He noted the V8 badge above the XJ6 badge astern.


Others have noted the distinctive V8 burble in the exhaust note.


Why buy the premium stuff if your engine does not need it? Politicos making fuel decisions. yowee....


Carl

 

In the USA, at least, I think you have a problem finding hoses that are not E10 compatible....because E10 has been around for so long. It varies by region but in my neck o' the woods (Pacific NW) E10 has been ubiquitous for at least 20 years

As for Jaguars, the owners manual or my 1988 say E10 is OK....so Jaguar was aware of E10 requirements at least that far back

Cheers
DD

 

I expect you guys know, but in case not in everyone's case, in Europe and the UK, octanes are rated in RONs (research octane number) whereas I have heard that in the USA the same petrol is rated in MONs (motor octane number), which gives a lower number for the identical stuff. A bit like centigrade and Fahrenheit. Quite often this causes confusion too.
Greg

 

Not quite.

Gas in North America, not just USA, is rated by AKI (anti knock index) which is the average of RON+MON.

We used the RON scale until the mid 1970s until some bright spark decided to confuse everybody. Owners of older cars (pre-mid 70s) sometimes get confused when they see mention of their old Ford or Chev needing 95 or 98, thinking they need to buy 'racing' gas to get that octane level.

Generally speaking there's a spread of 4-5 points between RON rated fuel and the AKI rating.

Euro 95 is identical in octane rating to N.Am 91.

 

I have used 89 octane in my 96 4.0.
I can feel a difference in performance and about 40 - 50 miles less per tank with the lower octane fuel.
I agree with SouthernGypsy about top tier fuels making a big difference. I make sure to run a tank of top tier at least every 3 fill-ups.

 

As reported recently by AAA, it takes several thousand miles of driving continuously with a TT fuel (vs. a cheap brand, if such a thing exists) for any difference to become apparent.

BP themselves says 5,000 miles.

Look it up.

 

Let's throw in a new twist.

They just opened up a new WA WA Gas Station. The place is packed.....Great Restaurant!!!

On to my point....They sell an 89 Octane w/o ethanol. They call it recreational fuel...for Boats, etc.

Would this be better than the 87 Octane w/ethanol...Probably....but what about the 93 octane w/ethanol.

By the way the recreational fuel is currently @ $2.65/US Gal. vs the 93 octane w/ethanol @ $2.79/US Gal.

Let's really get this conversation going!!!!!!!!


Happy Holidays

Softball60/Paul

1996 XJS 4.0L 2+2, 1989 Merc. 560SL 1957 XK140 Drop Head and every other British Sports Car known to Mankind