How nice would high octane gas be?

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Here in Australia the lowest octane fuel we have is 91. You can also get 95 & 98 which is what I put in my Demon with a 340. You can also get ethanol 10% but no petrol head I know of touches that crap fuel.
 
Building an engine that requires higher octane than what's available from the pump is totally unnecessary nowadays. WIth the great flowing heads that are available along with good intakes, and other smart parts choices make a high octane street motor kinda stupid, really. Save it for the race track. Even then, there are a LOT of pump gas race motors out there. Using race gas where it's not needed can even cost power.
 
I ran 87E10 in an 11.3 engine for two years with no problems.
I then swapped out the 292/292/108 cam for a 270/280/110 and reduced the Cr to 10.9, and ran that for two years, still on 87E10 still with no problems
I then swapped that cam out for a 276/286/110 and left the Scr alone, and still running that today 11 years later, and still on 87E10, and still no problems.
That is 15 years of no troubles.
During the first 5 years,every winter I took that engine apart and checked it out, and it had no fuel related problems.
That engine has Eddies on it and has run timing from 32 to 36. without problems. I run it at 32, cuz my but-dyno cannot tell the difference in power since it usually spins those crappy 295s to past the speed limit no matter what timing I have run.
I am at 950 feet here.

Maybe all that water is turning to steam inside my engine and that is why I have all this power. They say the power of steam is incredible. Naw I think not, my pistons and valves were always all carboned up, cuz I ran her a tad fat.You know, just in case somebody put too much alcohol in the batch.Or paint thinner.Or some other more volatile petroleum distillate.
I couldn't give a chit about octane.

But I can see the engine manufactures wanting to get a higher octane fuel, so they can run a higher Scr so they can get the same power out of a tinier engine. Yeah that's right; give us ever tinier engines that can barely hit 65 mph,forget about passing . Maybe they will just turbo everything. Then we can all buy new turbos at regularly scheduled intervals, and stay forever broke, hit by a double whammy of extra-high gas costs and higher maintenance costs.
Hyup, I'm glad I'm 64 this summer, and semi retired. I feel bad for the young people tho............They will have to work themselves to death, never making a final payment on anything.They may never actually own their homes. They will be paying interest till the day they die. They will buy a second hand car,on payments, and it will wear out before it's paid for. Anything else they buy is crap or will be in a few hours. They cannot afford children. There is no more joy in the world, for them, only work,work,work.
Oh sorry, I kindof got off track there for a second.......h
 
I do quite well on 85 here with 10% alcohol. The first sentence set the tone for the article.

That's not entirely true. In fact, it's more false than true. Lower octane burns faster and hotter while higher octane is less prone to detonation. Less prone to detonation because it's more stable and burns slower. As a result, less power is produced by the same volume. A good rule is to always run the lowest octane that you can get away with running. Some of you sea level guys may have a different philosophy, but it works just fine up here.
Karl, you are absolutely correct.... I am 100 feet sea level, and usually race ( my favorite spot, it's been a while ..) is 40 feet below sea level... 87 works fine, until you N2O, or add additional atmospheric... We are near 17-21 percent....( on pump gas, with alcohol additional additives..) Haven't driven the new small block combination yet, under fire....
 
Building an engine that requires higher octane than what's available from the pump is totally unnecessary nowadays. WIth the great flowing heads that are available along with good intakes, and other smart parts choices make a high octane street motor kinda stupid, really. Save it for the race track. Even then, there are a LOT of pump gas race motors out there. Using race gas where it's not needed can even cost power.

Agree 100%!! Not a single car manufactured today needs or wants more octane, and are designed to run on anything above what is commonly available! In the old days of big blocks and restrictive intake systems, more octane was needed to make the fuel burn longer, nowadays that is not an issue! A lot of the successful drag racers of today are using the E85, which is more stable, consistent, and very predictable! It's a science, and a science that is researched and developed with the very large dollars of the auto industry! Just pulling up to the pump and running higher octane, even in your high dollar motor build, is a guessing game, and almost always unnecessary!!

On the plus side, "racing gas" sure smells good, even my mom likes the smell of it burning!!! :)
 
I've seen quite a few guys at the track running on e-85, they say they need to watch out for corrosion, other than that they seem happy with it.
I have to run 110 on my 12:5 to 1 race motor and it costs $10.00 per gallon around here.

I was in college in Nebraska in the mid 80's when a few stations started offering "Gasohol". I don't remember what the mix was. What I do remember is filling my '73 Charger 340 with it and not getting 5 miles down the road before the needle/seat in my Holley carb would clog and flood over. Apparently it loosened up crud in the gas tank and sent it up the fuel line.
 
10% here and I've never had a problem. My winter storage procedure for the Cuda is to drive it into the garage and turn the key off. In the spring I pour a shot of gas down the carb and fire it up. I have never had a fuel related problem as a result of my winterizing procedure.
Not every car gets garage storage, some set outdoors, where they can get parked for the season & experience high 70's to sub-zero temps, heavy rains, melting snows &
the accompanying 100% humidity that goes with it. Tanks breathe, I've had cars get rarely used, drove them enough to maybe run a tank through em' if they were lucky.
Never had to worry until the last 8-10 years, now, even with the tanks full the fuel turns to s**t in no more than 1-1 1/2 yrs. & the interior of the tanks-senders-pumps are destroyed. I parked My Cutlass in the garage(unheated) and kept the tank full, started it & warmed it up once & awhile, as I gathered parts for it.....never an issue for a decade
during a move etc. . around '09 I decided to give it a good run in the early summer & a full fresh tank....and that was all she wrote.........by late next summer(unfortunately
all my cars got put on hold for personal reasons) when I fired it up it would barely run, a sample had the new dreaded cloudy look & I knew it was screwed.
The same for My turbo driver when the head cracked(previous owner got it hot once so....), sat w/a full tank (I was using this car daily & lots of miles) a year & a 1/2,
when I dropped the new engine I built in, had to drain & flush the whole tank & system....all cloudy s**t, never had that happen so bad so quickly ever in 2 1/2 decades of
playing with karts,bikes,& cars..... so whatever Dude.............................
 
I meant this thread purely for the guys like us, who may want the higher octane fuel. Not Moms Camry, that runs happy on below 90 octane.
 
thousands of these cars trade hands and the new owner has to work with what he has.
if you don't have a problem or are on the edge a little more octane is a safeguard,and regular gas can go sour as well and lose 2 or 3 points of octane.
 
Drained this last night from a Dirtbike sitting for a year. I would like to personally thank my Gubmt for this green cesspool.....

JW

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Did you use stabil before storage?
I took my car out for the first time a couple of weeks ago
and it detonated badly.It is Shell 91without ethanol from last Nov. and i used stabil.
..is stabil a croc like octane boosters, zinc,water wetter and all the rest?
 
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Did you use stabil before storage?
I took my car out for the first time time a couple of weeks ago
and it detonated badly.It is Shell 91 from last Nov. and i used stabil.
..is stabil a croc like octane boosters and zinc,water wetter and all the rest?

The ethanol formula works, as long as it's used while the gas is fresh. I prefer seafoam myself.

I take that back. I prefer 100% petroleum fuel, in which I never had to (pay more to) add anything.
 
The ethanol formula works, as long as it's used while the gas is fresh. I prefer seafoam myself.

I take that back. I prefer 100% petroleum fuel, in which I never had to (pay more to) add anything.

that was my point..i was using ethanol free shell 91.I have had regular gas go bad in stored roto tillers,and lawn mowers too.
 
that was my point..i was using ethanol free shell 91.I have had regular gas go bad in stored roto tillers,and lawn mowers too.

What was your point, but poorly made? You seem to argue points not contested and think it sound reasoning. You have heard plenty of first hand accounts and yet you seem to think they are fabricated as if it was some secret conspiracy among forum trolls. You are sure quick to gloss over the many negatives to tout the propaganda and junk science that surrounds the issue.
 
from the many posts there are those that have reported great results with ethanol blended gas used regularly and not stored for any length of time, but the bad results reported are usually from lengthy storage of ethanol blended gas.
My point was i have had ethanol free gas go bad as well from storage...and i used stabil which makes me think stabil doesn't work and neither do other additives.
..i thought this was all good info?
 
My 06 Suzuki ran so poorly on E10 that I had to rebuild the carbs (all four of them!) THREE TIMES in 6 thousand miles. This was a bike I bought BRAND NEW. It ate all of the O-rings in the fuel system, ate the petcock so it leaked, corroded the inside of the fuel cap with white powder, clogged the pilot jets over and over again to where the bike would not take part throttle. After the 3rd cleaning I changed all the jets and run non-ethanol fuel. No more problems! Bike is not lean anymore and it actually idled so much higher I had to turn it down 100rpm.
 
I haven't had issues with ethanol corrosion since I don't let anything sit with gas in the tank for more than a season or so (6 months?). Oddly enough I have also NEVER experienced any sort of rubber corrosion in the fuel systems on my '70 Duster, '88 5th Avenue, '93 Jeep Cherokee, our 12-year-old snow blower, 8-year-old lawnmower, whatever... However with the dry thin air here in CO fuel percolation is a BIG problem, worse than in other places with denser more humid air. If you have a carb'd car even with all the heat shields and spacers you can fit under the carb, if you let it heat soak more than 15 minutes there's no way it will hot start without holding the throttle open and cranking it for a long time to clear out all the gas vapors from the intake. That's really my only gripe with E10 fuel. There is a gas station that sells non-ethanol 91 premium, I may give it a shot in my '88 5th Ave because it has the factory Lean-not lean-Burn computer with knock sensor which advances the timing based on fuel octane.
 
You're not in an exclusive club there, it's happening here in PA as well. The 455 Olds I built is running a cold Torker intake(meaning I welded cast iron plugs in the heads), & it
started experiencing percolation even running to the point the idle was unstable, the eng. temp was perfect. Those heads & intake were on that car for over 20yrs., 1st w/an
800DP Holley, & the only change was to an HP950 Holley up top. After changing to a new & improved block/cam & exhaust/carb, it ran awesome, & had only touched up My
valve-job on the ported C heads. The next season the trouble started, resulting in boilover after parking one day, & a consequential carb fire on a restart attempt.......... He
added a carb plate style heat shield & so far it has been livable, but remember, this thing ran the same heads & intake from around '93 on & this cropped up about '08 so.....
I believe He just ran it at a flashlight drag here recently, so hopefully that is all it will take to be OK, the hood clearance is tight on those early Cutlass bodies.
 
that was my point..i was using ethanol free shell 91.I have had regular gas go bad in stored roto tillers,and lawn mowers too.
Sure You have, so have I, only it took YEARS to completely sour unless it was a very small partially filled container(such as a mower/tiller etc.). Now it takes no time because
of the highly accelerated oxidative nature of the ethanol mix, no to mention the absorption of water right out of the air drawn into the tank. My trusty & ancient '72 Gravely
sits out unheated every day of the year, and I would go out & fire it up every spring mow out 1/2 a tank, then top it of with fresh. Now i do it, but when I pop the cap, the
fuel has a cloudy look to it. My Pop bought it from the orig. owner in '76, I brought it out here in '96, that's how long & familiar I am w/this lawn tractor....& I am still using
it!! I earned money for My go-kart, YL1 Yamaha, AFX cars & track, & towards My 1st car, My '69 Dart Custom HT w/that thing!!!
 
All I can get in Topeka is 91 Octane. My car seems to run well on it, but I wonder if it would run better with 93. 340 with 10.75:1.
 
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