Flex-Fuel CB7 - Is it possible?

[crewfish13]

Flex-fuel is huge in the news right now, especially in the corn capial of the country (I personally come from O-hi-uh.) I've been reading up on it, and it seems that E85 fuel has an effective octane reating of somewhere around 105.

If flex fuel becomes readily available in the next couple years, how difficult would it be to convert a fuel system to handle E85, as you could have all sorts of fun with an engine knowing 105 octane fuel would be readily available.

[cp[mike]]

can you tell me a little more about it? ive never heard of it.

[crewfish13]

A lot of auto makers are marketing their new flex-fuel capable vehicles (GM's "Green/Yellow" campaign), which are vehicles capable of running off of either gasoline or E85 fuel. E85 is an 85% ethanol / 15% petroleum blend that's produced mainly from biomass (corn and sugarcane are the big sources right now). Basically the idea is start producing automotive fuel from domestic products. With a flex fuel vehicle, you can simply go to the pump and fill up on whichever fuel is cheaper. Gasoline in Ohio is alrealy like 10% ethanol, but I'm sure E85 is a completely different animal.

However, for all the conservation and evergy independence talk, I know that almost all high-performence vehciles run off alcohol. Pure ethanol has an effective octane rating of about 110, and E85 is about 105. That means monster compression capability on a properly built engine from readily available pump fuel.

However, I'm sure modifications to the fuel system would be required, although I think E85 can blend with gasoline in the tank, meaning you have a single tank, set of fuel lines, and injectors. I'm wondering what would need to be changed to allow your fuel system to handle a primarily alcohol fuel.

[v4lu3s]

i beleive the biggest concerns would be the fact that a petroleum fuel system is not going ot be ethanol resistant. most likely new fuel pump, fuel lines and injectors would need to be installed. there is a lot of information on it on google right now as well.

[v4lu3s]

also you need to remember that ethanol may have higher octane but it also has less energy than gasoline.

and also teh fact that tuning for ethanol and gasoline are very different so neither fuel would give the best power or economy unless you ran ONLY that fuel and tuned for it.

[Clueless]

also you need to remember that ethanol may have higher octane but it also has less energy than gasoline.

and also teh fact that tuning for ethanol and gasoline are very different so neither fuel would give the best power or economy unless you ran ONLY that fuel and tuned for it.

or had two ecu's and a massive switch to go between the two...

[teh win]

or had two ecu's and a massive switch to go between the two...

g00d point

[Accord R33]

or had two ecu's and a massive switch to go between the two...

actually...you would only need 1 ecu and a two chips.

[Clueless]

actually...you would only need 1 ecu and a two chips.

ooo...even better, maybe a black box for two chips and a remote switch on the dash to select chip one or chip two...

[Jarrett]

Good points. Yes, you would need to run just one fuel. About replacing your lines, that's a big issue with older cars converting to ethanol and propane due to the materials the lines nd components are made of but on more modern cars, the materials are suitable for ethanol use. That being said, given the age of a CB7's ines, it would probably be best to change over. V4lu3s is correct about ethanol having less energy. Of all the possible alternative fuel options we've been considering, gasoline still has the highest. Now, if you had a engine purposely built around the characteristics of e-85 then you would have a powerful clean burning car. It's definitely a better fuel for performance in a purpose built engine, but I think it's a process that's more involved than you expected.


Speaking of alternative fuels and their capabilities, there's a video on the internet of some guy in Texas runnoing a CNG dragster in the 7's. Running SUPER high compression.

[MRX]

Moates 2Timer - Two Program Switcher
(This little gem plugs into your 28-pin socket. It has a single wire lead coming off of it. Put a 27SF512 chip in it, and switch the wire lead to chassis ground to switch between two separate programs! Comes with one SST Chip )

nice huh

[Clueless]

Moates 2Timer - Two Program Switcher
(This little gem plugs into your 28-pin socket. It has a single wire lead coming off of it. Put a 27SF512 chip in it, and switch the wire lead to chassis ground to switch between two separate programs! Comes with one SST Chip )

nice huh

ooo...all the work done for you....I never seen it before though

[cloudasc]

From my understanding E85 is 85% ethenol and 15% unleaded gasoline, and there would be significant horsepower and torque gains by using e85 over race fuel, carcraft had an issue on it, but since it contains less energy then regular gasoline, it requires about 30% more fuel, this can be changed by either enlarging the jets, or programming the ecu to open the fuel injectors 30% longer.

Wouldn't you also need a high compression engine to run the high octane?

I think bisi's f22a insight would be a good canditate for e85!

[foamypirate]

You could run 30,000 octane in a 2.2:1 compression ratio motor. Octane does not impose compression requirements, it is the compression that requires the octane ratings.

[Leung]

i think a lot of the cars down in Brazil already flex fuel complient. i swore i read this thing somewhere that a lot of Fords down there use ethanol or when they leave the country they can run gasoline.


to the original poster, what part of Cincy are you from?