Interested to know what everyone is doing regarding running higher octane fuels in race cars. The highest octane available at the pump is 98 and I think there is a company doing 100+ fuels specifically for race applications.

what's the general thinking re high octane fuels?

There are heaps of options out there, not quite sure exactly what your asking though? Methanol or e85 can work out more economical for a race engine as some of the race fuels are super $$$$

The turbo rally cars in the ARC used to run 105 octane. Used to $5/L and the cars used to burn 1L every 2km at full pace and 5km/L on transport.

On Rally Q, which was 200 competitive, even for a front running state evo, the fuel bill $700 to 1k with spare fuel etc.

Most classes (inlcuding rally) seem to be going back to a pump fuel formula to bring costs down.

Av gas?
every time I go to a historic meeting they make sure to write in a source for Avgas for some of the proper race cars

Just go to the local airfield and see if they will sell it to you; there isn't much about these days because alot have gone over to jet fuel

I thought except for historic cars already running it, avgas was banned in motorsport?

Lots out there as said above. But depending on what it is, you may need to have a major retune. some of it goes off very qucikly too.

the question is, is the cost worth the extra power you will get?

I think you are right Bix, avgas is sort of banned but I read somewhere that avgas contains lead and this is why it is not allowed for racecars. However some historics have special allowances to use it. Also to buy so called racefuels you must have a CAMS license or similar.

To answer superowen my interest is mainly to do with track/sprints rather than methonal or E85, which is what the V8 are running now I think.

Seems to be a trend of guys with EFI cars converting across to E85... slight jump in power but significant lowering of engine temps.

Shell Racing 100 was popular until the stopped making it about 12-18 months back, so now most seem to be running BP or Caltex 98, some with BP100.

Avgas and Elf seem to be just down to the open wheeler crowd now...

Avgas I would steer clear of.... I work at an oil refinery and the ppe and controls we need to use when handling the tetra ethyl lead additive are just incredible. It's nasty stuff (especially to young kids) and has been phased out for a good reason.

The avgas you do get will likely be 100LL (low lead - dyed blue), unless you buy in WA, which is one of only a couple of places that high lead avgas (100/130, and dyed green) is sold. High lead avgas has twice the amount of lead as low.

Avgas is rated by MON (motor octane number) not RON (research octane number) so for comparison the various 98RON petrols around are about 88 - 89 MON.

thanks Doug, yes i did know about the different colours for the different levels of lead. I believe the avgas allowed for historics is the blue coloured fuel. my interest in all this is two-fold; 1st my subi engine in my racecar is a jap import and as I use the Subi ecu it is tuned for 100Ron fuel which is what I believe is used in Japan. 2nd I have a contact in Brisbane that blends fuel and can blend 100 or higher fuels and supplies some of the historic guys.

United Fuel sells 100 octane at the pump, I've run this a few times in my subi with Jap import motor and ecu and it works perfectly. And you're right they use 100 ron in Japland.

Here in WA Caltex 95 dips at 98.5 in the scutineering shed (which caused a bit of grief at first....... ), and Caltex 98 dips at 99 or 99.5 every time.

Which explains why Caltex are going broke..... Octane giveaway like that is bad business because the higher octane components (such as alkylate and reformate, which can be up to 105 Ron) are very energy intensive and expensive to produce.... These high octane blend stocks are the blended with low octane components (straight run naphtha, poly gas, cat cracked spirit etc ) to carefully meet whatever spec it is.

Not a worry mate.

United fuel could be from anywhere..... They have no refining assets so either purchase from oz refiners (bp, shell, caltex, Mobil) or import from o/s, ie Singapore, Japan, Vietnam, India.

Should all be compliant with your local spec though (different specs per state / region /time of year due to average temps and elevation).