Just thought I would chuck in a few opinions of my own that may help with a few issues that have been raised.
Earlier boost pressure. However the down side of this is that it aggravates any boost creep problems. Also for the same boost control settings there was an increase in boost (so the settings had to be decreased to achieve the same boost level)
This is due to the fact that the exhaust gases ethanol produce have a higher density. This helps with spooling time, but can cause boost creep as mentioned above. In most cases boost creep is caused by the wastegate port being too small and not allowing enough exhaust gases to bypass the turbo. So a larger wastegate should help with preventing boost creep.
Lower engine temperatures. On track testing showed the engine temps were brought right down to the thermostats temp and was almost operating too cold. We would look at either changing the low temp competition thermostat to a standard higher temp item or look at blocking of some of the air to the radiator if we were to continue with E85.
This is a bit of a touchy area as not only the running temp of water is affected, but so is the oil temp. I know of one vehicle having removed its oil cooler and changing from running 10w40 to 5w30 just to get around this. (I would suggest doing this as a last resort)
One way that should be able to help with running temp if it becomes too much of an issue, is to lean out the mixture to a point in which there is no denotation, or the risk of running to hot that its causing problems to the engine internals. This can be monitored via the EGT, but this will be put down to your tuner.
Build up of fuel in the sump and accumulation of fuel in the oil breather catch tank with E85.
E85 is less volatile than petrol meaning that it takes a higher temperature to make it evaporate. More fuel enters the sump with blow-by gases due to the fact that more is used and also under cold start and while the engine is warming up. The engine and engine oil needs to be above 78C to get the E85 to boil of and leave the sump at a reasonable rate (this is compounded by the fact that the fuel makes the engine run cooler). Also once it does leave the sump it condenses in the cooler catch can and builds up in the can.
This can be one of those undesirable effects of running ethanol, but isn’t to much of a problem if monitored. There is several ways this can be tackled, but these sometimes aren’t the best way for motorsports. One way involves using a Fuel Recovery System which forces the ethanol in the oil system to condense in a separate container which is then plumbed back in to the intake system. Other than that, the only other thing I can suggest is to just check your catch can.
Well I hope this can help people out. If there is any confusion or question just ask and ill try to help as well.
