I've been using it in my Redline Sedan for about 3-4months now. Your choices are Caltex and United. There are slight differences between the two brands which i'll detail below:
Caltex (E-Flex): Is quoted to be 70-85% ethanol depending on the season (the colder it is, the lesser ethanol content in order to ensure perfect cold starts). The lower ethanol content is apparent as it burns a lot slower than the united blend. I average 12.8L/100km @ average of 62km/h.
United (E85 by CSR): Is always 85% ethanol (and has been rumoured to have a little more from time to time). You can 'feel' the difference between this and Caltex's E-Flex; United feeling like it has more power. This would probably be accurate as it also burns faster. I get on average 14.2L/100km @ an average of 60km/h. I've also run my car on a fair dyno with only a VCM OTR and united E85 in the tank and it made 232rwkw with an A6.
A little pros and cons list:
Pros:
- Smells amazing (as noted by Bonners).
- Definitely a power increase (however can be slight depending on the grade/level of ethanol).
- Much cheaper at the bowser.
- Exhaust tips don't get dirty! (That's my favourite part
)
- Emissions have very little carbon in them (environmentally friendly)
Cons:
- Burns faster.
- Can be inconvenient to find.
From my basic calculations, assuming E85 costs $1.20 and PULP98 Costs 1.55 (a 35c difference):
E85 from caltex:
costs $1.20 x 70L (a full tank) = $84.
It burns at 12.8L/100km, thus 70L gets you [(70/12.8)x100]= 540km.
$84/540km = 15.5c per km.
PULP 98:
costs $1.55 x 70L (a full tank) = 108.5.
It burns at 10.1L/100km, thus 70L gets you [(70/10.1)x100]= 693km.
$108.5/693km = 15.6c per km.
As you can see, at these prices, E85 is cheaper by 0.1c per km.
Conclusion: It costs exactly the same to use E85 as it does to use PULP 98.
* ALL FIGURES HAVE BEEN QUOTED USING A A6 6L SEDAN WITH AFM ENABLED, A VCM OTR AND A KPM CATBACK. NO TUNE *