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Octane Supreme

An Octane Booster that really works!

It's that simple !!!!



No more leaded fuel -

What do we do now??

Protect your classic or performance vehicle by using the fuel additive it was designed for.

First - some basics
The "explosion" that takes place during normal combustion is merely extremely rapid oxidation (or burning) of the fuel / oxygen charge.

High compression ratos used with lower than required fuel octane can cause a disturbing "pinging" ("knocking") noise as the fuel charge "explodes" rather than being initiated by the controlled spark plug, resulting in extreme cylinder pressures.

In fact it has been established that the flame front advances 10 to 12 times faster when "knocking" at approx. 250 - 300 m/sec.*1 At detonation it can go as high as 2000 m/sec. So we enter the uncontrollable zone where it usually ends in tears.

With the discovery that lead additives could modify this behaviour lead to the widespread adoption of tetra ethyl lead (TEL) additive in the fuel to increase the fuel's octane rating. Compared to fuel treated with other anti-knock agents, "ethyl" treated fuel produced more power and greater fuel efficiency.

Two of the greatest advantages of TEL over other anti-knock agents is that very low concentrations are required and TEL is highly soluble in fuel.

Typical formulations called for 1 part of ethyl fluid (prepared TEL) to 1260 parts untreated fuel.

Of equal importance is the wear protection afforded by lead oxides and lead sulfates on valve seat surfaces. These protective deposits (solid lubricants) are only formed through the use of leaded fuels with adequate lead content.
Engines built to run on leaded fuel rely on this protection against wear.

A brief History

When these engines were designed, manufacturer’s took advantage of the performance benefits of a high compression ratio. The increasing compression ratios required higher and higher octane fuel to eliminate pre-ignition (or “pinging”).

For years tetraethyl lead (TEL) was added to petrol. In the post-1945 era, as compression ratios increased, TEL became an essential component in all grades of petrol, with up to 1.05 gms/litre.

100 (RON) premium was about 0.7-0.8 gms/litre and 94 (RON) regular 0.6-0.7 gms/litre

In the UK 5-star grade was up to 0.8 gms/litre in the 1970s (unobtainable by the early 1980s). By the end of the 1990s, the TEL content of UK 4-star grade petrol was 0.15 gms/litre.

Even the humble MG B with only 8.8:1 compression ratio requires high octane fuel.

The Drivers Handbook (p.31) states:

"Owing to high compression ratio of the engine, fuels with an octane rating below 98 are not suitable."
“It is necessary to use Super grade fuels in the 100-octane range unless premium fuels of minimum 98-octane (Research method) are available."

In the 1960’s some fuels had as much as 3.0 gms/gal.(US) (0.79 gms/litre).
Allowable levels in the 1980’s dropped to 0.1 gms/gal.(US) (0.03 gms/litre).
In 1976 the EPA(USA) ordered the gradual reduction of lead levels in fuel.

In Australia
In Australia, during the ’60s & ‘70s leaded Standard fuel was 90 / 92 octane (RON), with high grade leaded Super fuel of 97 / 98 octane rating up to around 100. (XL brand petrol was reputedly 100 +).

For enthusiasts seeking higher octane, alternatives were readily available:
BP sold - Benzol,
Shell sold - Methyl Benzene,
Neptune sold - Toluol

Some service stations had bowsers for dispensing these fuels. Others had bulk drums “out the back”.

Performance enthusiasts with HIGH COMPRESSION ENGINES were spoilt for choice.

With the mandatory introduction of catalytic converters (in an endeavour to lower engine emissions) leaded fuel was withdrawn from the market.

TEL adversely affects catalytic converters and sensors. Exhaust sensors can be rendered useless in minutes. Therefore unleaded fuel was introduced. Engine manufacturers re-designed valves and valve seats to cope with Valve Seat Recession (VSR) now the lead protection was removed.
At the beginning of 1995, Victoria and NSW governments lowered the maximum lead content of leaded petrol. The other States followed by the end of 1995. Super grade leaded petrol was withdrawn from the market in 2001.
The elimination of lead content caused a loss of at least two octane numbers requiring other changes in the refining or blending of fuel.
96 octane was considered adequate for most vehicles by legislators.

Owners of pre ’86 cars were advised to use Lead Replacement Petrol (LRP) - basically regular unleaded fuel with VSR additive.
LRP fuel octane rating was low at 91 (and in some cases up to 95).

HP OS Image 2 copyright (c) 2012.

Many different substances were tried and some are still available. Above image shows build up!!
Not so good for engine breathing!!!

Mobil and Caltex used Manganese11, Shell used Phosphorous12, and BP used Potassium13.

Overseas and local tests have shown:

11 Manganese additives - resulted in fouled spark plugs in less than 1,000 kms.
Phosphorous additives at the levels required to prevent valve seat recession would cause corrosion problems.
13Potassium based additive at four times the recommended level, valve adjustments were required at only 2,000 kms and some cylinder heads were worn out at 10,000 kms.
Sodium based LRP, experienced serious valve wear at only 1,000 kms.

In any case, LRP wasn’t enough for our performance engines.

One oil company spokesman openly stated that LRP was not suitable for highway use, (in other words, higher rpm and loads) and they sell syringes of their additive to put in your tank!

In 2005 LRP was phased out. Thankfully, according to many engine builders. This phase destroyed many engines.

No product could offer the full advantages of the lead it was supposed to replace.

Performance vehicles suffered as the fuel octane was nowhere near that required by their 60’s & 70’s high performance engines.
Apart from the reduced octane, the greatest effect of the removal of lead was the potential for engine damage.

Older engines with cast iron cylinder heads need protection from Valve Seat Recession(VSR).

In the past, this protection was provided by the minute quantities of Tetra Ethyl Lead in the fuel. Without such protection, microscopic particles of cast iron melt and deposit themselves on the (harder) exhaust valve face. Over a period of time, the valve seat erodes (termed “Valve Seat Recession”) and the head is progressively damaged with subsequent loss in power.

When unleaded fuel was introduced (91 octane), engine manufacturers re-designed valves and valve seats to cope with Valve Seat Recession (VSR).

Engines designed and built to run on leaded fuel depend on the wear protection provided by lead oxides and lead sulfates on valve seat surfaces. These protective deposits, or solid lubricants, are only formed through the use of leaded fuels with adequate lead content.

Some engines were detuned to “just run” on this fuel or enthusiasts moved to using Avgas.

Octane Numbers
In pump fuel the two octane numbers are MON and RON ratings. Determined by tests conducted at different loads and speeds. In the US, octane is rated as (RON+MON)/2, also known as the fuel's sensitivity, or Anti Knock Index (AKI).

There are two octane numbers for each fuel, in aviation fuel, one for lean mix and one for rich mix, rich being always greater. So, for example, a common British aviation fuel of the later part of the war was 100/125.
TEL is still in use today as a component of 100 octane aviation fuel. The current formulation of 100LL (low lead) aviation fuel contains much less lead than historical aviation fuels did.

By the end of WW2 American aviation fuel was commonly 130 to 150 octane, which could easily be put to use in existing engines to deliver much more power by increasing the boost delivered by the superchargers.

In addition, TEL is st ill in use as an ingredient in many racing fuels. Why? Because, to date, this additive is unsurpassed in its ability to increase octane numbers.

In times gone by, Avgas could be purchased from some service stations, airports and spares outlets. This practice is also no longer an option - it is now unlawful to use Avgas on public roads with heavy penalties.

The EPA (USA) claimed that no meaningful damage would be done by the use of unleaded fuels in engines designed for leaded fuel, despite the fact the EPA had never conducted tests on the effects of unleaded petrol. In 1985 US Congress forced the EPA(USA) to test engine durability using unleaded fuels in engines designed for use with leaded fuel.

So what did the EPA discover?*3

And why weren't the test results widely publicized?

The EPA tested eight engines, only two are of interest to the motorsports or performance enthusiasts. The test was conducted for a total 200 hours on each engine using a commercially available unleaded regular fuel. To this base blend tetraethyl lead was added to create blends with 0.1 gms/gal.US (.026 gms/litre). and 1.2 gms/gal.US (0.317 gms/litre).

The completely rebuilt stock engines were run-in for 12.5 hours using leaded gas (1.2 gms/gal.). After break in, new OEM heads were fitted for the actual testing.

After testing with one type of fuel, the heads were removed and inspected and new fresh heads were fitted for the next cycle of testing. The heavy duty engine was a GM 454 equipped with hardened valve seats, designed to be used with unleaded.

When tested for 200 hours using leaded (1.2 gms/gal.US) petrol, none of the valve seats showed recession in excess of 0.007 inches.

The 454 with induction hardened valve seats showed valve recession measuring from 0.007” up to 0.032”. The 200 hour test would be the equivalent of about 10,000 miles at a constant speed of 50mph. Catastrophic engine failure can take place when the valves recess about 0.060” to 0.080”.

A second test was run with low lead fuel, (0.10 gm/gal.US), pump fuel. At the end of 200 hours of testing there was essentially no recession of the exhaust valve seats.

Next test was run with unleaded fuel,heads were fitted with hard valve-seat inserts, - after 200 hours of testing, valve seat recession was fairly consistent across all valves with a maximum of 0.017”.

Also tested was a GM 292 six cylinder engine with cast iron (soft) valve seats (designed for leaded fuel). When tested using unleaded fuel the test had to be discontinued after only 88 hours when one of the valve seats had recessed 0.099”!

The EPA / GM test simulated road load conditions that reflected the use of a relative large truck at highway speeds, lower speeds of urban type driving and near maximum speed and load conditions. These testing cycles were repeated 16 hours per day for a total of 144 hours. At the end of the 144 hours, a steady state mode of 100hp at 3000 rpm for 16 hours per day was used until the 200 hour mark was reached.

Testing of this sort on a dyno is considered quite aggressive, reflecting full bore acceleration and heavy hill climbing, with high coolant temps. In real life constant hill climbing and constant hard acceleration would not be possible, after all, after every hill there's a downhill and after every straight there's a corner.

Another independent test found an average of .060” (~1.5 mm) recession in 12000 miles when run at 70 mph. The extent of valve seat recession is very dependent on engine load.

Many studies have concluded that most damage occurs under high-speed, high-power conditions. Moderate operating conditions, and low to medium speed engines under moderate loads do not suffer rapid recession.

Under severe conditions, damage occurs rapidly, usually with significant cylinder-to-cylinder variations on the same engine.

What can be concluded ??

Although the EPA (USA) declined to publish any conclusions from their tests, the results speak for themselves.

With the following conclusions:

1. Engines designed for leaded fuel are at RISK when running unleaded fuels.

2. Engines fitted with either induction hardened seats or hardened seat inserts can survive on a low lead diet of 0.10 gm/gal. US (0.026 gms/litre).

3. Even engines with induction hardened seats can suffer damage when subjected to unleaded fuel.

Only with TEL can you expect the highest performance in these crucial areas.

Petrol as a medicine
Before internal combustion engines were invented, fuel was sold in small bottles as a treatment against lice and their eggs. In those early times, the word "Petrol" was a trade name.

This treatment method is no longer common, due to the inherent fire hazard and risk of dermatitus.

Dangers of LEAD

Undeniably, lead and the associated scavenging agents used in TEL are regarded as highly toxic.

In large quantities, exposure to these chemicals can have some negative effects on our health. Like other petro-chemical products it should be handled with due care. Lead is meant to go into the fuel tank, not on or into the human body.

Would you let your family come into contact with it ??
You may be in closer contact than you expect.
Especially the female members of the family.

Long lasting and brilliantly coloured lipsticks may contain Lead. *2

If Lead is so deadly why would anyone smear it on their lips?? HP OS Image 3 copyright (c) 2012.

To test for Lead:
1. Put some lipstick on your hand.
2. Use a Gold ring to scratch on the lipstick.
3. If the lipstick colour changes to black,
then you know the lipstick contains lead.

Canned food products in steel cans with soldered joins - solder has a lead content.

Some paints have lead added. Recently some imported children’s toys were found to have paint containing lead.!!!!!!! And we are all familiar with children’s habit of putting toys in their mouth.

Other properties of leaded fuel
TEL's biocidal properties help prevent fuel contamination and degradation from bacterial growth. The coating of lead and lead oxide from using TEL would quickly accumulate and destroy an engine if lead “scavenging” additives were not introduced at the same time.

Hard starting ??

The lead in leaded fuel helped to catalyse carbon burnoff during engine warm-up. Now that lead has been removed from the fuel, carbon burnoff (self cleaning) requires a higher temperature.
…without lead, the spark plugs can suffer fouling more quickly, especially if the engine is running rich.”*4

Often this fouling cannot be cleared and spark plug replacement is the only solution.

Other additives in leaded fuel.

Fuel, as delivered at the pump, contains additives to reduce internal engine carbon build-up, improve combustion, and to allow easier starting in cold climates.

One of these additives - Sulphur - has been gradually reduced in unleaded fuel, resulting in a much reduced “shelf life”.
Major oil companies estimate that a half full tank of unleaded could be unusable in as little as 2 months.

Sulphur was added as a preservative to slow down algae growth in fuel. Without it, the algae grow and the fuel quality deteriorates. When asked about the shelf life of unleaded fuel, BP Technical Support Line answers: “One month”.

After one month in a half full fuel tank (ie: unsealed, plenty of air space) you would notice a drop in power.
After three months, the car would be hard to start, would not idle well, and would suffer a significant loss of power.
By this time, much of the high volatility elements in the fuel will have evaporated, leaving the more dense part of the mixture.

In addition, the fuel will be oxidizing and fungus will be growing.
The fuel takes on an orange colour and gets progressively darker as time goes by.”

HP OS Image 4 copyright (c) 2012.
Fresh fuel on left. 8 month old fuel on right.*5
It also “stinks”.

Running a performance engine on “stale” fuel can result in serious piston damage. This kind of damage is usually caused by detonation, from either:
ignition timing advanced too far
fuel mixture too lean.
insufficient fuel delivery rate
low octane or poor quality fuel.

Detonation - results!!!

HP OS Image 5 copyright (c) 2012.

Fresh race engine after 3 qualifying laps.*5

Higher octane = More power??
Some people believe that adding a higher octane fuel to their engine will increase its performance or lessen its fuel consumption;
this is false
engines perform best when using fuel with the octane rating they were designed for. The higher the octane number the greater the fuel's anti-knock capability. Using higher octane fuel permits the use of higher compression ratio without having problems with knock. Compression is directly related to power, so engines that require higher octane usually deliver more power.

High-performance engines are generally designed with a high compression ratio associated with high octane numbers, and thus demand high-octane fuel. It might seem odd that fuels with higher octane ratings burn slower, yet are associated with more powerful engines.

For comparison only,
the following should be of interest:

BP Premium Unleaded is 96 RON, 84 MON*6
Latent heat of evap. is 0.34 mJ/kg.
BP Ultimate is rated 99 RON, 88 MON*6
(and does NOT contain Ethanol)*6.
Latent heat of evap. is 0.34 mJ/kg.
BP 100 Racing fuel is rated 110 RON, 100 MON*6
Latent heat of evap. is 0.36 mJ/kg.

It should be noted that the power output of an engine also depends on the energy content rating or the specific gravity of its fuel, which bears no simple relationship to the octane rating.
It is assumed the greater the density, the more BTU's are packed into the fuel.

Therefore, octane has no relationship to exhaust valve recession, or the fuel's ability to vaporize or even the power available. Here we rely on TEL!!

[*1] Source: Robert Bosch Automotive Handbook
[*2] Source: Dr. Nahid Neman, Mt. Sinai Hospital, Toronto
[*3] Source: Kiyoshi Hamai - Chapman Report - November ‘87
[*4] Source: BP Fuel news - June 2005
[*5] Source: C. Dodds - Sprite Parts
[*6] Source: BP Fuel news - January 2010

**NOT to be used in engines designed to operate on UNLEADED fuel.
(i.e. fitted with exhaust sensors, catalytic converters etc.)

**Maximum inclusion rate MUST NOT EXCEED 125mls/10 litres fuel (200mgms/litre Pb)

***Can only be sold to members of recognised motor / water sport associations or clubs***.
***Copy of current club membership card required.***

**By Legislation ALL States and Territories of Australia
***Recognised by the Australian Government under the Fuel Quality Standards Act 2000.

Now Manufactured in Australia

Click here for
Material Safety Data Sheet (summary)
(544kb in PDF format)