1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

Using low-lead gasoline

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Old 08-19-10, 04:02 PM
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Using low-lead gasoline

Is there any known issues with using a low lead (110 octane) fuel in a rotary that has no emissions? Will the small amount of lead do any long term harm? Just curious.

My memory tells me that the lead just killed the cat - but I wasn't sure about the sparkplugs, etc. Just not sure if it will gum anything up or if the engines have been designed differently since the we went to unleaded.

(mental note- I'm not talking about leaded fuel, but low-lead) I plan on hitting google up but thought I'd check here for opinions.
Old 08-19-10, 04:14 PM
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i think you're right, lead will kill the cat, but you're in FL so you probably don't have one.

it might also shorten the spark plug life? other than that i don't see any problem with it...

piston engines like it cause it keeps the valve seats from dying, but we don't have
Old 08-19-10, 05:50 PM
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The whole point of "unleaded gasoline" was to make the world safe for cats... plug fouling due to lead 'ash' with older fuels was about the same as plug fouling on modern fuels, as I recall.

In general, NA rotaries prefer lower, not higher, octane. Our long skinny combustion chambers have enough trouble with flame-front propagation time as it is, without slowing the burn further. Tetra-ethyl lead increases octane, which slows the burn rate.

Using leaded gas in a street car in the US is also a federal crime... maximum $10,000 penalty if caught....
Old 08-19-10, 05:56 PM
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Legalities notwithstanding, would'nt the lubricating qualities of the lead help address the need for lubrication in / around the cumbustion chambers of our engines?
Old 08-19-10, 07:19 PM
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Originally Posted by rwatson5651
Legalities notwithstanding, would'nt the lubricating qualities of the lead help address the need for lubrication in / around the cumbustion chambers of our engines?
Not what it was for; strictly was created as an anti-knock compound. Wasn't enough of it in gasoline to have any lubricative value; was mixed in at something like 1000:1
Old 08-20-10, 07:01 AM
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Unless your boosted, lower octane is what you want in a rotary. Also rx7s had
the unleaded only sticker so it may cause some internal issues with the engine
but maybe not. Our motors are pretty tough.

The lack of lead in modern gas is hard on valves in older, pre non-leaded gas cars.
In particular it caused early valve seat failures due to the metalurgy used for the
valve seats back then. It will also kill a cat quicker as mentioned.
Old 08-20-10, 07:44 AM
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I'm planning a turbo swap in the near future and was looking for some alternate fuels for high boost applications/testing. The car will be primarily a track car, so no worries about DOT regs. Its really the anti-knock feature I'm interested in with the LL fuel. So it seems my memory was correct - if I find any new info as I search, I'll post back.
Old 08-20-10, 09:24 AM
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Interesting question. From wikipedia (http://en.wikipedia.org/wiki/Gasoline):

Lead

The mixture known as gasoline, when used in high compression internal combustion engines, has a tendency to autoignite (detonation) causing a damaging "engine knocking" (also called "pinging" or "pinking") noise. Early research into this effect was led by A.H. Gibson and Harry Ricardo in England and Thomas Midgley and Thomas Boyd in the United States. The discovery that lead additives modified this behavior led to the widespread adoption of their use in the 1920s and therefore more powerful higher compression engines. The most popular additive was tetra-ethyl lead. Its use continued for decades despite the deaths of several members of the original research teams from lead poisoning. Marketing materials purposely avoided mentioning lead explicitly, and instead "Ethyl" was used. However, with the discovery of the extent of environmental and health damage caused by the lead, and the incompatibility of lead with catalytic converters found on virtually all newly sold US automobiles since 1975, this practice began to wane (encouraged by many governments introducing differential tax rates) in the 1980s. Most countries are phasing out leaded fuel; different additives have replaced the lead compounds. The most popular additives include aromatic hydrocarbons, ethers and alcohol (usually ethanol or methanol). In the US, where lead had been blended with gasoline (primarily to boost octane levels) since the early 1920s, standards to phase out leaded gasoline were first implemented in 1973 - due in great part to studies conducted by Philip J. Landrigan. In 1995, leaded fuel accounted for only 0.6% of total gasoline sales and less than 2000 short tons (1814 t) of lead per year. From 1 January 1996, the Clean Air Act banned the sale of leaded fuel for use in on-road vehicles. Possession and use of leaded gasoline in a regular on-road vehicle now carries a maximum $10,000 fine in the US. However, fuel containing lead may continue to be sold for off-road uses, including aircraft, racing cars, farm equipment, and marine engines.[16] The ban on leaded gasoline prevented thousands of tons of lead being released into the air by automobiles. Similar bans in other countries have resulted in lowering levels of lead in people's bloodstreams.[17][18]

A side effect of the lead additives was protection of the valve seats from erosion. Many classic cars' engines have needed modification to use lead-free fuels since leaded fuels became unavailable. However, "Lead substitute" products are also produced and can sometimes be found at auto parts stores. These were scientifically tested and some were approved by the Federation of British Historic Vehicle Clubs at the UK's Motor Industry Research Association (MIRA) in 1999.[19]

In some parts of South America, Asia, Eastern Europe and the Middle East, leaded gasoline is still in use. Leaded gasoline was phased out in sub-Saharan Africa effective 1 January 2006. A growing number of countries have drawn up plans to ban leaded gasoline in the near future.
Old 08-20-10, 09:40 AM
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Originally Posted by Keith13b
I'm planning a turbo swap in the near future and was looking for some alternate fuels for high boost applications/testing.
E-85. Done.
Old 08-20-10, 02:18 PM
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Originally Posted by Directfreak
E-85. Done.
Care to explain? You seem to be a big proponent of E85; but I have been trying to stay away from the ethanol....unless I'm drinking it!

Why are you so PRO E85?
Old 08-20-10, 03:25 PM
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Originally Posted by Keith13b
Care to explain? You seem to be a big proponent of E85; but I have been trying to stay away from the ethanol....unless I'm drinking it!

Why are you so PRO E85?
E85 - runs muuch cooler. Has in intake air charge cooling effect like Methanol, without the bad effects on your fuel system. Lower Ermissions.
Much less chance of detonation, You can run much more advance timing.

Race Gas = 116 octane, at $12+ per gallon.

E85= 105~110 octane at $2.50 per gallon or less.
(Cheaper than regular unleaded)

Available almost anywhere - literally "pump gas".

It fully puts "race gas" in your daily driver for less than
"regular uneaded". It has revolutionized the high HP
Turbo setups in the last two years.

No More "acohol injection"
No More "water injection"
No More Overspending on Race Gas.

All the benefits of race gas, for the price of regular gas.

The only downfall, less fuel economy, less MPG.

Read up:
http://www.raceone85.com/
http://www.modified.com/tech/modp-09...torsports.html
http://www.turbomagazine.com/newslet...hur/index.html
Old 08-20-10, 06:27 PM
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+1 E85. If you're running a MS2 setup, you can find a fuel-type sensor to plumb into the supply that will automatically shift your Stoich point and fuel map based on what blend of E85/RON-85,RON-87 your engine is actually getting. Cool. E85 is 1.80 a gal in Colorado.
Old 08-21-10, 04:47 AM
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I've been considering E85 for a few years now. I drive my car fairly long distances, and I'm always concerned that I won't be able to find it when I'm away from home.

I live in MI, and there are a few stations that have it . . . but most of them don't.
Old 08-21-10, 01:10 PM
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Any places in Florida selling E85? If you know of any - please post.
Old 08-21-10, 02:21 PM
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Originally Posted by Keith13b
Any places in Florida selling E85? If you know of any - please post.
Save the link and keep checking here as they keep adding on.

e85Refueling.com
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