E85 modifications

[mead6082]

Hi all
we are using E85 for first time this year.I want to know what necessary changes must be made on the ecu and fuel system. i would like to know what materials withstand ethanol's corrosive properties.
Thank you in advance

[mead6082]

Hi all
we are using E85 for first time this year.I want to know what necessary changes must be made on the ecu and fuel system. i would like to know what materials withstand ethanol's corrosive properties.
Thank you in advance

[RenM]

why do you keep posting this question and why the hell are you going to use e85 if you have no clues of whatsoever what consequences (pros and cons) it has for you.

This forum is not for someone else to make your work!

[t21jj]

Reposting the same question that you already asked will not help your cause any, especially one that is just down the first page still. Also if you have not yet I'd suggest you use the find button and search the topic it's one that's been also discussed many times. We are not going to give you a magic solution. If you can't handle the basics of the fuel maybe you should stick with gasoline.

[Thrainer]

Have a look at the ATZ Formula Student special and you'll find an article about our conversion to E85. It's mostly from a thermodynamic point of view, though.

[Thrainer]

Article about our E85 conversion in ATZ:
http://www.amzracing.ch/amz/files/amz1384.pdf

[AxelRipper]

Its very simple. anything that is not stainless steel in your lines will corrode... i highly suggest using braided or hard stainless steel for all of your fuel system. this includes the gaskets in the carb/intake and the engine. its best to just throw them away, then assemble the engine and caulk all of the cracks EXACTLY 3 times over! this is the magic number, and very important! any less, and you have leaks, any more, and it can collapse under its own weight, which is of course horrible for formula cars.

as far as the tuning modifications, due to the higher octane, therefore slower and colder burn, there are a couple modifications you should make. first, shave the head so that there is no chamber left in it. this may require some valve work, but it is completely worth it. you will also have to get a new piston that is clearanced for the valves. trust me, this bumps up the compression which is KEY to making power with e85. you also need to put as much fuel into the engine as possible, due to the power density of e85. turbos can help with this. if you set an injector to spray right on the intake turbine, it will vaporize the charge more effectively, allowing for you to run more fuel. a constantly spraying injector or multiple injectors per cylinder would probably work the best here, because of the massive amount of fuel that you have to run to make it work properly. dont worry too much about adding more air, since 1.) the turbo helps with that and 2.) there is more oxygen in e85 than in gas

of course with the fuel comes the spark. if you put more fuel, you obviously need more spark to fire it. a good rule of thumb is 1 high output coil per spark plug per PAIR of valves. so for most engines that are run in formula competition it is advisable to have 2 plugs per cylinder in order to fully ignite all of the fuel. these need to be the highest quality, hottest plugs you can find at your local auto stores... be sure to shop around so you know you have the hottest ones, just to make sure that they can ignite the fuel properly. MSD coils are also very good, as they usually come as high power as you can buy without having custom ones made, which if you're making a permanent switch you may want to look into.

oiling is also a major issue if you switch to e85, due to the corrosive properties of the ethanol. it wipes away the oil on the cylinder walls more than other fuels. the use of the turbo should help a little, due to the oiled bearings which tend to add some oil to the intake charge. you should look at either running straight or slightly diluted lucas oil additive in your engine. it sticks to the moving parts better. or you could consider finding a way to hide an oil injection system similar to that of a 2 stroke in your intake somewhere to make sure that the pistons are well lubricated.

so really, its a pretty simple thing to do... dont worry about it... anyone could toss it together the week before comp and it should run just fine as long as you dont have any intake plenum. the restrictor/throttle body should be immediately before the turbo, and that should be connected to the intake on the head, possibly built right into the cylinder head if you're running a single.

I hope i helped out some http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

[Adambomb]

All good things http://fsae.com/groupee_common/emoticons/icon_wink.gif

Another thing to consider is that exhaust temps can be pretty severe, even with cool burning E85. May just want to make the fuel tank and all lines our of Inconel, just to be safe. And hard coat anodize everything, including your catch cans (which should also be Inconel), as E85 blow-by turns anything else into powdery mush. Exhaust turbines on the turbo should be made of pure Rhenium. I know it's sort of hard to find and expensive, but totally worth it. If you can swing it, not a bad idea to make the turbo housing out of Tungsten. (OK, I had too much fun in non-ferrous metals class)

Also, if you're running a single, the exhaust pulses can be pretty severe. Running two turbos effectively splits the pulses in half though, so that's a good idea. Also doesn't hurt to run a turbo and a supercharger (or even better, 2 turbos and a supercharger).

As for the coils, I recommend the MSD Blaster 2. They have screw terminals, so it's easy to daisy chain them together. Also wouldn't hurt to run 2 coils per plug (splice the two coil wires together in parallel using those twist connectors normally used for house wiring). Also, E85 has been known to have troubles with cold starting, so glow plugs and/or an intake heater is recommended. In fact, building some ducting around the exhaust to make your own Thermac system that uses exhaust heat to pre-heat the intake air is a good idea.

It may sound like a lot of work, but it is pretty simple, and something that can be taken care of in just a few days. The best strategy right now would be to focus on driving practice with driving games. I recommend Mario Kart, as it has the best physics.

[/sarcasm]