Unleaded fuel (1 Viewer)

What grade of gas do you run

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[quote author=IDave link=board=1;threadid=13500;start=msg124961#msg124961 date=1079935587]
Oh, yes, and while we are on the subject of gas, could someone knowledgeable weigh in on the topic of ethanol blends? I understand that they tend to cause leaner running regardless of octane rating. That might be good (if it is correct)for those of you who have trouble with overly rich exhaust measurements. Any harm in gasahol?
[/quote]

Is gasahol cheaper than regular gasoline? Where would you even get the stuff?
 
E-10 is 10% ethanol. It runs about .02 cheaper here in Nebraska, and I don't think you could find a gas station around here that didn't have it. The two negatives I have heard on E-10 is vapor lock, and running ethonal in an old fuel system losens the crap in the gas tank, and you'll plug some fuel filters. I've never ran regular unleaded in my 40, so I can't judge any difference.
 
Woah. That's what you meant by E10. Duh. Ok, well. I don't know about the rest of the world, because my corner here is so small, and I don't get out much. But we have 1 guy who sells E10 from an unattended station with a Sinclair sign over it. His 92 octane E10 is at times 22 cents a gallon cheaper than the 91 octane down the block, and I think the regular is about 15 cents cheaper. He happens to be an aquaintance, and if I lived in that town (it is actually 30 miles away from home) I would support him for sure.

Sounds like the E10 would be a good way to clean out your tank! (Then change out the fuel filter.)
 
I run 87 octane. I have tried the higher grades, but I can't tell a difference. At times I do develop a pinging. I have found that 16 oz. of B-12 chemtool in the gas at fill up will clear it. It must be some water or other junk getting in the tank. B-12 clears it up great. Don't use it too often or at high concentrations as it damages your gas lines. The cheaper the gas, the better it is in my wallett's opinion.
:cheers:
 
IDave - on the leaded gas thing - the only reason gas was leaded, back in the day, was that the lead acted as a lubricant for your valve guides. Years back, I had converted the head on my TR6 to run unleaded, and the only thing I had to do was put in different valve guides. That head wound up getting screwed up (overheating) and I had to get another one, but because of the economics of it all, I went with the standard head. The mechanic I got it from told me that it really wasn't that big of a deal to run unleaded in a non-converted head (it was a worry, I couldn't find leaded gas anywhere at that point) - if I recall correctly, unleaded gas still has lead in it anyway, just not as much.

One side note: when I was in high school, driving the TR6, I could only get low octane leaded gas, so, to up the octane, I'd mix leaded and unleaded. I know it sounds crazy, but it worked like a charm...and I had it confirmed by my chemistry teacher, who was also an ex motor cross racer - he said they'd do that with their bikes for the higher octane.

And, for the record, I had been running 87 octane in my Cruiser for a while, but the timing was retarded, and it ran fine. Once I set the timing, I got the pinging, so I added a half tank of 89 and a can of octane booster (which is supposed to give you another 4 points) - so with that concoction, I'm guessing I'm at about 89. It runs so much better, too.
 
I work in refining so I am familiar with some of these questions. Octane ratings vary by altitude with the higher altitudes using 85. Most of the country uses 87 as the regular grade. The octane rating set by the engine manufacturer is all you need. Cruisers need regular, corvettes need premium. If your engine pings with regular, I would think there would be something wrong with it - timing too advanced maybe. Premium is only needed for high compresion, high performance engines. The BTU content of regular and premium is the same so I don't see anyway that premium would give better mileage. One of the big benefits of using lead back in the old days from the refiner's viewpoint is that it provided a big octane boost. A couple grams of lead would change a regular to a premium. Too big of an environmental problem though.
 
IDave - on the leaded gas thing - the only reason gas was leaded, back in the day, was that the lead acted as a lubricant for your valve guides. Years back, I had converted the head on my TR6 to run unleaded, and the only thing I had to do was put in different valve guides.

That makes sense. I'm running a set of updated bronze guides in my cooper 'S' head as well. :cheers:
 
Unleaded fuel (gasahol)

I tried gasahol about 10 years ago in a honda civic and had pinging problems come up in about 7 months - switched back to straight gas and some gas treatment and the pinging slowly went away. I can't help but believe that it was from the gas (it was Beacon/Ultramar). I would hope that they have reformulated it by now, but I haven't used it again since. Probably won't have a choice soon.

I heard that even though it helped vavle guides and seats, leaded fuel made more corrosive combustion byproducts - ate out exhaust systems faster, contaminted oil faster, and was one of the reasons that up until the 70's it was unusual to get 100K out of an engine - I remember rebuilds after 80K were not uncommon (remember when the odometer only had five digits?). I don't know how much truth there is to that; it would make some interesting research. I know that Detroit engine building methods have improved a lot since the 60's, partially in response to the quality that Toyota and Co. introduced to the market.

A buddy of mine who was a chemical engineer told me that there was a big battle between the chemical industry and the farm lobby in the 20's about which anti-knock compound to use in gas - ethyl lead (chemical industry) or ethyl alcohol (corn farmers). Guess who won?
 
I run 87 octane in my '72 FJ40's "F" engine and in all of our cruisers, '88 FJ62 and my '93 FZJ80! No problems except some pinging in the '88, but I think that may be tuning related...

When I rebuilt the '72 "F" engine, my machinist suggested putting hardened exhaust seats in the head to handle unleaded gas and last longer. We did it and I don't have any problems running any gas in Buddy now-a-days.
 
[quote author=cpip link=board=1;threadid=13500;start=msg125044#msg125044 date=1079968632]
The octane rating set by the engine manufacturer is all you need. Cruisers need regular,[/quote]

So in Colorado where the regular is 85, but the book recommends 87, Does that mean mid grad and not regular? or do you adjust the recommended down by 2pts(??)
 
Well, I might try gasahol again, but I am shy of it because I certainly ran rougher with the 1 tank a week ago. I did like how the exhaust pipe carbon went away. But, maybe there were other factors and I should try it. Perhaps since I have lean jets for altitude, the combination of the smaller jets and the ethanol resulted in just too lean a mixture overall.
 
Dave- do you have to take the carb out to swap the jets. I haven't looked to see what kind I have, but I remember your earlier research were the spare jets are already stored in the carb.

Ken
 
Ken, you do have to take the carb apart to change out the jets. After doing it, I realized that I could possibly have taken the carb apart and switched out the jets without actually removing the base from the manifold. But it would be somewhat awkward. IIRC, the smaller jets are stored in the carbs up to a certain year, then not, but I don't remember the cutoff. It was in a thread on Pirate, if you want to do a search.
 

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