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110 octane fuel

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Lin

Lin

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I have recently moved to Florida. When in Virginia I always purchased ethanol free 92 or 93 octane fuel. I cannot find any 92 or 93 ethanol free fuel where we are in Florida - most have 90 - but a local station does have 110 octane (I have not checked the price). I donā€™t know a lot about this subject, but I think of 110 as racing fuel. I have a Dennis Welch fast road aluminum head (hardened valve seats) on my BT7 engine with HD8 carbs and a BJ8 camshaft. What is the ā€œgroup thoughtā€ on using the ethanol free 110 for road use? I really hate to start using ethanol fuel to get the higher octane rating. Thanks for your insights.
 
Lin -

I run my extra 110 race fuel in my stock '65 BJ8 and it loves it, really comes to life. I can get pure premium ethanol free 93 octane which is what I usually run, but when I have extra 110, I run 50/50. You might try a marinia must boat tanks can't hold ethanol for too long. Sunuco 110 is $8.99 here in the PNW, that's a little steep to run all the time.
 
Here on the coast of NC I run 93 octane non-ethanol fuel in all of my English cars (2 Healey's and a Jag), and it works fine in all. About 2 years ago, for about a 3-month period, the highest non-ethanol fuel I could get was 90 octane, and I could really notice the difference. I started buying 100+ non-ethanol aviation fuel at a small private airport facility and started mixing it in a combination I thought would bring the total up to +/- 93 octane. I can't remember exactly, but I think a 1-gallon mixture included somewhere between 8 to 12 percent of aviation fuel. Another advantage for some would be the fact that aviation fuel still contains lead. The cost per gallon of aviation fuel at the time was about $4.50/gallon, which was much less per gallon that the racing fuel that was available here.
 
Google "ethanol free gas florida" and your problem may be is solved, there are dozens of stations available up and down both east and west coasts, although not necessarily in your town.
Be aware both marine and airplane fuels are lacking in some necessary additives for automotive use as both power boats and small planes run at mostly fixed rpm and are not stressed as are automotive applications.
 
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Lin--

The main reason that race engines need high octane fuel is to prevent pre-detonation (knocking). Engines with high compression are more prone to knocking. Also pre-detonation is more likely to happen when spark advance is increased. I use 93 w/ethanol in my car which has a DW head and cam with no ill effect and while you may prefer non-ethanol fuel I think that using 110 (about $9-$10 per gallon) is simply a waste of $$.
 
When I am traveling outside California I fill the tank here at a special station in Westchester with 98 octane premium fuel. I will also use it if found on the trip.

In town here in LA I use the Shell 93 octane ethanol fuel with no problems.

Years ago a Healey writer and racer from Plano Texas provided a formula for mixing 110 octane with 93 to obtain 98 octane fuel , Reid may recall his name??
 
When I had Denis Welsh make my aluminum head, I had the combustion chamber sized for 92 octane, the standard premium in California. It has been fine.
 
I run pump premium - with or without ethanol; whatever's available - and have never, ever noticed any difference or had any problems with brand, age of fuel, presence or amount of ethanol or octane rating variation. Just "because" I try to fill up at Chevron or Shell stations, but haven't noticed any difference when I have used off-brand stuff.

Several years ago I got on a no-ethanol kick and used only ethanol-free leaded premium for a time - there was a station that had it that was not terribly far from where I garaged my cars at the time - but never noticed any difference and eventually quit inconveniencing myself.

Guess I'm leading a charmed petrol life.
 
Hi Lin
in Italy 100 octane gasoline are present in some gas station - I use it - cruring my dieseling at engine stop (due to the H compression)
No evident problems are observed - car run very well, with it - sometime I add the additive for green gas
 
Hi All,

Michael's point on the purpose of Octane should be considered before paying the extra cost for fuel with high octane.

After 3 or so years in the life of my BJ8, I had a head gasget issue and after pulling the head, brought it to a machine shop to assure it was flat. Being young and inexperienced, I made a mistake in my instructions to the machinest and asked to have .060" shaved rather then the .006" I intended. As a result, high octane fuel has been required for my engine. As it turned out, although my engine's compression had increased by this mistake and running at the high end of timing using a Crane electronic ignition, I am able to freely wind my un-rebuilt engine to 5K before shifting with no pre-ignition on 91 Octane fuel commonly available in NJ.

Years back, it was easy to secure 100 octane or even 110 Octane at many local stations and the price difference was much higher then regular gas but at significantly lower costs then today. I can still get 100 Octane ethanol-free fuel at a nearby station, however, at more then 3X the price of 91 Octane and at my Healey's 14 MPG, I could afford to do little more then go, fill-up, and come home.

Ray(64BJ8P1)
 
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Editor_Reid said:
I run pump premium - with or without ethanol; whatever's available - and have never, ever noticed any difference or had any problems with brand, age of fuel, presence or amount of ethanol or octane rating variation. Just "because" I try to fill up at Chevron or Shell stations, but haven't noticed any difference when I have used off-brand stuff.

Several years ago I got on a no-ethanol kick and used only ethanol-free leaded premium for a time - there was a station that had it that was not terribly far from where I garaged my cars at the time - but never noticed any difference and eventually quit inconveniencing myself.

Guess I'm leading a charmed petrol life.
Click to expand...

My experience as well. I do go name brand/'top tier' if possible, but if you're a 100 miles from nowhere in the Nevada desert you take what you can get (I was at Rachel, NV--near Area 51 and 100miles from either Tonopah on the west or Caliente on the east--one time and some guys going to an off-road event came in low on fuel. I heard them say they'd pay 'anything, ANYTHING' for a couple gallons of any grade. Still don't know if they made it). Agree running higher octane than the engine requires to avoid detonation is an absolute waste--although the oil companies would like you to think otherwise--but a modern, computer-controlled, injected engine--the antithesis of all but a few Healey engines--can squeeze a little more power out of a higher octane fuel, but only up to a point. It appears that most brands are putting in adequate quantities of cleaner additives in all grades.

Try as I might, I have not found any detrimental effects of 10% ethanol in the fuel, and any mileage difference has been inconsequential in my BJ8 in over 150K miles of mostly cross-country driving.
 
Just ran across this thread and figured I'd mention that I make sure I've got non-ethanol fuel in the tank and through the carbs before storing it for the winter. And - yeah, it's criminal, but I just fished our BJ7 out of its storage this morning.... Doug
 
twas_brillig said:
And - yeah, it's criminal, but I just fished our BJ7 out of its storage this morning.... Doug
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Wow, up where you live that must give you about 2 weeks of driving before you have to put it up in storage again. :smile:
 
The closest ethanol fuel station is 140 mile freeway round trip from home. That would give me max of 60 miles of pleasure driving before I had to refill.
 
I really see no point in putting 110octane in a Healey unless its a heavily modified race engine . All you do is increase your combustion temperature and heart stress on the exhaust valves and blow a whole lot more $$$ and hot air out of the tail pipe . JMHO
I run mine of whatever the station carries and usually only put in regular grade fuel which contains ethanol .
 
steveg said:
The higher the octane number, the cooler it burns.
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Im not buying that , higher octane means higher temps the get more umph on the combustion stroke .
 
Higher octane means that the fuel burns slower so the charge doesn't detonate. The higher umph comes from the engine mods.
 
Quick google search
 
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