E85

[daniboy]

ok so has anyone tried e85 in a sportivo corolla? i have done a lot of research into it and it appears to be pretty unreliable with its octane rating due to being mixed with different batches of fuel.but in saying that it ranges between 96 and 106 octane depending on the actual blend. The other concern i had was according to a few sources it is not so nice on plastics and rubber like normal petrol,and our whole filter and pump assembly is rubber and plastic!

Im running a japanese 2zz and ecu out of a fielder and it seems to ping on even ultimate,

[Noodle Boy]

to use it you need to convert a few bits and pieces such as the fuel injectors to make it compatible with e85. i wouldn't recommend using it due to what you said about it being not nice with plastics, but with the fact that it condenses into sugar(high sugar content from ethanol) in the engine, fuel lines ect.. if the car isn't used for a long time, which isn't convinient, meaning the components need to be changed.

[Ronnyboy]

It comes down to Personal choice, personally i wouldnt recommend anything below 91....

[Keisari]

to use it you need to convert a few bits and pieces such as the fuel injectors to make it compatible with e85. i wouldn't recommend using it due to what you said about it being not nice with plastics, but with the fact that it condenses into sugar(high sugar content from ethanol) in the engine, fuel lines ect.. if the car isn't used for a long time, which isn't convinient, meaning the components need to be changed.

This seems to be a popular myth, yet I've not seen a mechanism for how this is supposed to happen.

Ethanol cannot spontaneously 'condense' into sugar. One way it is produced, and the most common way for petrochemical applications, is by the fermentation of sugarcane. The ethanol is obtained by distillation (sugar cannot be distilled, and so stays behind. In fact it decomposes somewhere around 250 C instead of undergoing phase transition to gas). The distillate contains water, which can then be further distilled down to 5% and drying agents used from there.

Put another way, if the ethanol in my lab spontaneously became sugar, there'd be surprised and angry phone calls to the supplier.

It is true that high ethanol concentrations are incompatible with some plastics, especially some rubber seals, and so the fuel system needs to be redesigned to work with it.

[Keisari]

It comes down to Personal choice, personally i wouldnt recommend anything below 91....

In this case, 85 is in reference to the volume fraction of ethanol, rather than the octane number.

[Guest]

you cant run E85 in a sportivo without having a pfc/adpatronic/etc that is tuned for it... E85 is a higher octane than normal petrol, but also requires a lot more to injected

[SuperDave]

The stock ECU will be trying to keep the AFRs at 13:1 or so, the ethanol in a blend up to 85% will require a lot more fuel added to counter the leaning out caused. Stoich of petrol is 14.7:1 as you probably know, and for ethanol it is 9:1. So at a guess you'd need to aim for about 9.8:1 for stoich on E85. Again, as you most likely know, you need to run a little richer than this to stop the detonation and cool the cylinder.

[CHA54]

If you're going to run E85, I'd strongly recommend an ethanol content sensor to be plumbed into the fuel system and then wire it's output to an aftermarket ECU that can modify the maps to suit the actual ethanol content of the fuel.

A very expensive and time consuming process to first get setup with the sensor, pump, injectors and aftermarket ECU and then spend all the dyno time doing the 4 or 5D mapping of fuel and ignition on different blends to get it perfect.