This was research done with a actual chemical lab, not someone just saying what sparked knocked in a turbo car engine, base your buying on research done at a independant lab, if you read the results you can base your purchase on factual information. Also looks as if 104 has changed their recipe as of late

.There is absolutely tons of information to be found on this subject. Make your own conclusions.
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For this test we tracked down nine different makes and models of octane boosters, two fuel "additive," a straight race fuel and a drum of Toluene. Where there were several different "levels" of octane boosters in the one brand, we chose the strongest version.
The biggest claims the bottles have is the amount of "points" they claim to increase. This is ambiguous as a "point" can relate to either 1.0 RON (Research Octane Number) octane points, or 0.1RON octane points.
The list of entrants in our octane Olympics included:
STP Octane Booster
Wynns Octane 10+ Power Booster,
Amsoil Series 2000 Octane Boost,
Super 104+ Octane Booster,
VP C5 Fuel Additive,
ELF HTX 330 Racing Fuel Stabilizer,
Nulon Pro Strength Octane Booster,
PowerFuel Super Street Nitro Based,
PowerFuel Max Race Nitro Based,
NF Octane Booster Racing Formula,
NOS Octane Booster Racing Formula,
Toluene,
VP Motorsport 103 Unleaded Racing Fuel
THE TEST
To conduct these tests we contracted independent laboratory Intertek Testing Services, who would test our products on a knock engine.
We had to also find a base fuel to add our boosters to so we went to the closest public petrol station, a Shell on the outward-bound side of the Westgate Bridge in Melbourne.
Being a performance-based test, we chose premium unleaded fuel as this represents the most common high performance fuel (ie: if you start with regular unleaded, you’re wasting money!). We should add that "some" boosters would have improved the octane rating of regular unleaded proportionately more than our tests with PULP.
With a RON rating at a minimum of 95, we first established the exact octane of the PULP. The biggest surprise was our randomly select Shell resulted in a quite high 96-8 RON.
We precisely measured and mixed each additive to the PULP, according to each manufacturer’s recommendations and specs and poured each into the knock engine’s tank. The compression ratio was then slowly increased until it started to knock, gaining a threshold of detonation and subsequently a maximum RON rating.
Of less importance but still worth mentioning is the design of the bottles: since most people will be pouring it straight into a tank, the design of a bottle is important to prevent any spillage on paintwork causing damage.
So let’s look at the results!
THE RESULTS
BASELINE OCTANE 96.8
Octane points
It’s very easy to confuse octane ratings as there are a number of separate international standards. MON (Motor Octane Number) is the number derived from a fuel when it’s applied to a test engine run at 3000rpm rather than 600rpm and higher inlet temps and ignition advance. The Australian importer of 104+, Andrew Holdsworth, suggested MON is seen as a more real-world test.
Though none of the fuel companies promote the MON figure which is normally between 7 and 10 numbers less than RON (Research Octane Number).
Intertek’s Graeme Marks believes RON provides the general public with an idea of which additive works more effectively. And being the most commonly-used reference, we’ve used RON for all our tests.
11th
PowerFuel Super Street Nitro Based
946ml treats 35 litres RRP: $35
Right from the start, we were told PowerFuel’s additives weren’t necessarily octane boosters, but horsepower helpers. We kept this in mind when testing both the products, but of the two only the Super Street claimed it was specifically designed to increase the octane rating of PULP. With a 20-percent nitro mix, Super Street Nitro-Based still improved octane ever so slightly (0.2RON) but the real test for these two would come on the dyno runs.
OCTANE IMPROVEMENT: 97.0 (+0.2 RON)
10th
PowerFuel MaxRace Nitro Based
946ml treats 35 litres RRP: $45
Containing another 15 percent more nitromethane than the SuperStreet formula, MaxRace doesn’t claim to increase octane, but the verbal recommendation was the same, ie: its main characteristic is to boost horsepower, not octane. For a fair comparison of these two additives, you need to look at the power they produce. As for octane, it proved very similar toe the SuperStreet formula bumping up octane ever so slightly.
OCTANE IMPROVEMENT: 97.0 (+0.2 RON)
9th
STP Octane Booster
350ml treats 57 litres RRP: $10.95
One of the cheapest of the group, the STP was also one of the hardest to find. Auto stores either didn’t stock it, or had simply run out! Claiming to increase the octane 2-5 points, in a well-designed-for-pouring bottle, the STP – used in the ratio determined by the label - improved the octane marginally by just over half a point. A little disappointing unless you interpret STP’s claim actually meant 0.2-0.5 points. Then it’s a good result!
OCTANE IMPROVEMENT: 97.4 (+0.6 RON)
8th
Wynns Octane 10+ Power Booster
325ml treats 60 litres RRP: $10
The Wynns was the cheapest of the lot and claimed an increase between two and five points, again not actually listing what a "point" related to. Strangely though the 10+ could indicate 1RON and if this is the case going by our tests it almost lived up to its name. It didn’t quite live up to its claims however, increasing the octane rating by 0.8RON.
OCTANE IMPROVEMENT: 97.6 (+0.8 RON)
7th
Super 104+ Octane Boost
473ml treats 83 litres RRP: $25.95
The acknowledged winner of all previous testing in this country, Super 104+’s bottle stated we should expect an increase between four and seven point. With a new formula introduced about 12 months ago, identified by an "Eagle" logo on the back of the bottle, the Super 104+ seems to have lost its edge with a marginal gain of just less than 1.0RON.
OCTANE IMPROVEMENT: 97.5 (+0.9 RON)
6th
VP Racing C5
355ml treats 75 litres RRP: $19.95
VP has a strong reputation with fuels and its high octane formulas are very popular (VP?) with drag racers. VP Racing’s C5 Fuel Additive lacked any indication of contents nor claims, but the C5 additive still provided a reasonable increase of 1.3RON.
OCTANE IMPROVEMENT: 98.1 (+1.3 RON)
5th
NOS Octane Booster Racing Formula
355ml treats 60 litres RRP: $28
NOS, a relatively new octane booster, comes in "1/10th" scale bottles designed to emulate the actual nitrous bottles of its successful NOS systems. The Racing Formula is the strongest of three concentrates and containing Hydrotreated Aliphatics and Methylcyclopentadienyl Manganese Tricarbonyl (try saying that 10 times in a row), it contains a lead replacement which NOS claims increases the octane rating by as much as seven points. Obviously not recommended for street use, it also included with a handy pouring spout. In testing, it proved a good result improving the octane rating by almost 2RON.
OCTANE IMPROVEMENT: 98.6 (+1.8 RON) as much as 7 points
also looks as though the quality of the 'pulp" fuel will have a impact on it as like we all know, we are getting junk these days, pay more and recieve less and less quality as well!
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