Has anyone considered going one of these routes?
Subscribed. I know nothing of this sorcery or how to apply it reliably to a B8.
I don’t know if it has to be strictly for the track, I would say keep it open to tuning the car in general to those fuels.
Looks like Solo is pretty much your only option for both types of these tunes atm.
Considering you would normally run 100oct:
Definitely would be a plus for the fuel cost for both.
There will be a plus for E85 and Meth in terms of keeping the IATs down.
I don’t really see any issues with either if the car is properly tuned for it.
You’ll need a pit crew to fill you up halfway through every session lol. E85 likes to burn away fast.
This is an excellent point. You’d have to bring E85 fuel jugs with you to the track (or plan out a mid-day refueling trip), that doesn’t sound particularly fun.
I haven’t and likely wouldn’t due to lack of availability. The amount of fuel consumed during a road course event is quite high so lugging around jugs is your only option unless e85 is available nearby.
E85 is more hyped up then it’s worth. There are lots of plus and lots of minus sides of it. Tried E85 in my cobra and it wasn’t all its cracked up to be. You get a lot of excited but not educated people talking about it. If you want E85 to blend with your gas that’s OK but you can’t blend too much as its not good to throw off the mix.
Water meth injection is nice if you have a 15 year old Honda or an older turbo car but it’s not great for adding a true octane improvement.
Looking into home made or barrel bought race gas to mix still is one of the best options. When you do the math on the cost of E85 vs how much more the car consumes it. It’s not a great deal. Or not that I or lots of the other cobra guys have found.
Thanks for the thoughts so far. It’s starting to sound like E85 may be more trouble than it’s worth (re lugging fuel) and there aren’t many tune options for it right now anyway so perhaps that conversation might be better served after more E85 tunes see the light of day.
What about using standard 93 or 100 octane tunes with methanol or water/methanol injection though? It seems like this might be beneficial for keeping power consistent on a hot day or after heat soak has set in. Any thoughts to that regard? I know a few folks have done this already just not sure anyone has done it with lapping sessions in mind.
FWIW I use a full tank of 100 octane in 60 minutes of on track time
It’s helpful if you understand that methanol and ethanol (e85) are used in most race gas mixes. So the big draw for those two is using them for there ability to remove heat. Well almost all race gas is very effective at removing heat. It just isn’t something that people talk about. Usually the dominant conversation about race gas is its huge octane and power rating. But in race gas is a huge ability to cool down the motor and the intake charge. That’s why e85 and water meth never produce better results then race gas.
So is the only reason people use E85 is because it’s 1/3 the price of 100 octane race gas?
WUT! Cool info. Never knew this.
Is it possible to simply run race octane gas on a stock tune? I suspect yes.
I ran 100% E85 in my b5s4. It wasnt wort running all the time in the car, Since the fuel is 20% less efficient, i only got around 160 miles per tank. It was a pain to keep filling up every couple of days cause i drive so much.
When you calculate it out, it does cost more to run daily than 91 oct, unless gas prices are back into the $4 range as e85 doesnt fluctuate with oil prices.
It runs the engine extremely cold, if you pop the hood you can put you hand on the engine and its cool to the touch. Also if you are catless there is hardly any odor emitted from the exhaust.
It does have its +'s, if you are a street racer its the fuel for you.
I have had good results just mixing e85 with 91 in my s4 and using the 100map. Its amazing how much difference it makes.
Here is a very good calculator for mixing (bottom one) http://www.intercepteft.com/calc.html
you can but there’s a level where it’s not helping
Good info in this thread, thanks all! Interestingly I am now inclined to just run a race gas tune and forget about E85 (for my purposes anyway).
This also brings up another interesting concept, has anyone geared a race gas tune towards keeping the engine cool and keeping power consistent throughout a lapping session? I don’t necessarily want short term max power, I want consistent power throughout a 25 minute session and I want to keep my oil and coolant temps in check.
Also, I have been reading about methanol installs on other platforms and have generally come to the conclusion that achieving a well sorted methanol setup for the track (road course) might be more trouble than it’s worth. If someone came out with a well-sorted kit for our platform though, that might be a different story (not holding my breath).
One of the reasons I like running race gas from the $9 pump at the track is it doesn’t have ethanol, unlike the other gas in California. I’m not sure if that was founded.
About 3 hours north of San Francisco there is a county that has a few race shops that sell MS109 and Sunoco GT 260 Plus. I may need to make a run.
Clear lake?
Did you happen to run straight E85 and an E85 specific tune in your Cobra? I’m curious what other downsides there were if so.
I’m actually kind of liking the idea of E85 again simply because I could run it all the time and show up to the track with it in my tank already (as opposed to trying to achieve an empty tank on arrival at the track for a race gas fill-up). Carting 4 x 5-gallon jugs of E85 to the track wouldn’t be that bad right? Granted I am carting a lot of stuff already.
E85 is the least used fuel of all fuels so you never know how long it’s been sitting in the tank and e85 is a magnet for water. Seriously standard fuel doesn’t attract water like e85. So you have to worry about how much water is in the mix. Then there are aggressive winter mixes with way less content. Over all the wonders of E85 come into play if you don’t have a well built system. Once I upgraded my cooling system on my cobra I couldn’t tell much of a difference between the pump tune or e85 tune. I could however tell the difference between the e85 and race tune. The race tune was monster.
If your going to tote 5 gallons of anything make it 5 gallons of real race gas.
I hadn’t heard about the water attraction and stagnant fuel considerations yet, good to know. The primary pump I would use is in a highly populated area, though I know that doesn’t guarantee fresh or well stored fuel.
Regarding the lower ethanol content fuels, I don’t think that’s a problem here in Texas but I would still likely run an ethanol content monitor and gauge to be sure.
The Texas heat is another reason I’m interested in E85, lots of discussion out there about its cooling capabilities. I know you’ve mentioned that race gas can have this effect also and perhaps with sufficient cooling its less of an issue. Also, thanks for sharing your experience with your Cobra.