ELF Race Fuel - in stock ! [Archive] - SpecialStage Forums

: ELF Race Fuel - in stock !

04-28-2010, 09:00 AM

This is a new announcement, but some of you might already know this (from seeing things around the shop, etc.):

As some of you already know, or have known, we have switched a few of our major customer cars from our old type of fuel to a new type of fuel, since late last year. We did this after significant back to back dyno testing of four different fuels on the same car, with each fuel tuned to get the most out of the car. This originally was done at the request of a manufacturer, who was trying to get us to look at trying different fuels.

Based on the above tests, we decided to import a full container of one type of fuel, from Europe (the tests were THAT positive). We then tried that fuel in the full systems (to make sure things like fuel cells, filters etc. weren't going to have issues like they do with another popular brand of fuel used in the USA). And since then, we've been using it in our top 3 cars since early January.

We originally only imported this product for in-house team use, not for retail sale. However the recent "run" on another fuel (which we also sell) has made us re-consider and we decided to now offer this to the open market.

There are three Elf products we are carrying in stock:

Elf Turbo Max - FIA fuel, useful if you 'get a map' from an ECU or car from Europe/Australia/Asia or want to be safe to run internationally. This was the "hot" FIA spec fuel for many years (and still is). This is a high specification, reliably consistent fuel.

Elf Perfo 100 - In Europe they use RON + MON / 2, so actually, this is more comparable to something like most US spec "103" or "104" (most of which dont use both numbers). The RON number is 109 ! HOWEVER, this is MORE STABLE than the current popular brand *and* has two distinct advantages: 100% legal for Rally America by weight, and NO ETHANOL. And it also has power gains over the competitive fuel !

Elf Perfo 105 - Again, this is a RON + MON /2 number, this is more comparable to a "113" or "114". The RON number is "113" ! This is MORE STABLE than the current popular brand and has three distinct advantages: 100% legal for Rally America by weight, NO ETHANOL, and no MTBE !! This fuel has SIGNIFICANT power gains over the competing fuels.

PM for pricing. We have over 4000L in stock.

05-10-2010, 05:48 PM
The US does use (R+M)/2

05-11-2010, 12:38 PM

Have you ever bought a drum (or tuned with) a drum of the most popular brand of race fuel sold in Canada (and about half the folks in the US) ?

We aren't talking about country specific generalities

We are talking about a fuel

"Branded 109" - RON 109
"Branded 109E" - RON 109
"Branded 100" - RON 100

Elf Perfo 105 - RON 113
Elf Perfo 100 - RON 109

The only popular/common unleaded race fuel sold in the US which brands itself with an octance number which is RON+MON/2 is Sunoco, which is their GT+/GT brands (104 and 100). That GT+104 is RON 109 BTW.

So yes, maybe the USA does use RON+MON/2, but someone should tell the marketing guys and all the people buying the "109", but its not the point anyways. The new fuel is different/better in several key areas:

no ethanol
RA legal specific gravity
more oxygen
more RON

You can drop in replace the common "109" with Perfo 100 and the timing is going to be the same, we've shown that on the dyno.


05-11-2010, 12:48 PM
You can see the specs for yourself here:


on a bone stock PGT 2.0L WRX already tuned to the max for pump 94 with restrictor, with Elf 105 and tuning alone (no other parts) you will gain +/- 75 ft. lbs of torque !

As stated the Perfo 100 is a direct drop in replacement for the "109". Minimal or no tuning changes required. For the Perfo 105 you do have to re-tune.


05-11-2010, 08:27 PM
There's no need to jump on me. Some of your statements were a little inaccurate and I was trying to clarify. RON and MON are different parameters of a fuel and they are measured using different tests. (R+M)/2 (or Antiknock Index, AKI) is just a convenient way of listing a fuel's resistance to knocking. That is why pump fuel is listed as such. But, as you pointed out, you can have the same AKI for different fuels but it is possible for them to have different RON and MON ratings.

Therefore, because they are different parameters, it is important to list both (or one and the AKI), which many race fuel manufacturers do.

Since there are so many variables that will affect the performance of an engine, the best way to determine if one fuel is better than another is to test it, which you have done. RON, MON, and AKI are simply indications of how a specific fuel has behaved in a test engine under specific conditions relative to predetermined standards. They are to be used as a guide for the knock characteristics of a certain fuel under general conditions and only testing will determine how exactly that fuel with behave in a specific engine under the desired conditions, i.e. racing or on the dyno.

05-12-2010, 12:36 PM
The statements aren't inaccurate.

In Europe it is ILLEGAL to market a fuel's octane number as anything other than RON + MON /2.

In the USA it is LEGAL and COMMON PRACTISE to market a fuel's octane number as just RON.

Its IMPORTANT to explain this to the layman (who isn't prone to regurgitate google and wikipedia, and other incomplete internet information) who, when faced with a decision:

"The new fuel is 105, but mine is 109"

"Well, yes, that is the label on the drum, but really, your 109 is lower octane than the 105, if it were measured the same way, your 109 would be 104"

"And never mind that, there are the other points as well..."

without clarifying WHY this is the case, its pretty easy for the layman to get confused.

THIS IS WHY IT IS IMPORTANT TO POINT OUT THAT IT WOUL BE ILLEGAL TO MARKET the popular "100/103/109" as "100" or "103" or "109" in Europe.

And that the Elf "100" and "105" is indeed higher octane (if anyone was asking) than the 100/103/109 currently available on the market.

FYI, your conception of euqally applying RON and MON for the knock index is common practise, but RON matters more in these applications. Generally speaking, high energy molecules are associated with low octane numbers. That's why formulators have to make compromises between energy and octane numbers. RON only describes the anti knock index. Even at the same RON+MON/2 (which they aren't), the new fuels still win.

05-13-2010, 10:11 AM
what about the rating in a turkey's gizard? :o

Nice research and informative information.

Take it for what is worth guys, I for one learned something new today. Thanks RR.