I did mention in my previous post that road cars retune AFR for E10 using the lambda sensor.
The gain from recalibrating a road car for E10 would be almost unmeasurable.
afaik ....
Isn't that just mere discoloration from high temperatures? (More like thin film interference colors*) I'm quite sure I saw such with welds and stuff.PlatinumZealot wrote: ↑17 May 2022, 17:35Strange colouration on the crown.
I don't think the piston is steel. Too chunky to be steel. Some sort of coating on it though.
Tempering colors are produced when steel is heated and a thin film of iron oxide forms on the surface. The color indicates the temperature the steel reached, which made this one of the earliest practical uses of thin-film interference.
I have never seen heat discolouration on pistons before. But then again i have only pulled apart street car engines. Someone else who does high performance engines is better placed to say if this is normal.mzso wrote: ↑21 May 2022, 13:12Isn't that just mere discoloration from high temperatures? (More like thin film interference colors*) I'm quite sure I saw such with welds and stuff.PlatinumZealot wrote: ↑17 May 2022, 17:35Strange colouration on the crown.
I don't think the piston is steel. Too chunky to be steel. Some sort of coating on it though.
Edit:
I see this not at the related wikipedia article:Tempering colors are produced when steel is heated and a thin film of iron oxide forms on the surface. The color indicates the temperature the steel reached, which made this one of the earliest practical uses of thin-film interference.
From friction inside crank sump. Interesting. Makes sense. I assume 110-120C operating temp of those engines would cause almost heat threat those pistons. Further i would assume they don't use squirt system! Because i think then we would see uneven discoloration under crown of piston.
Ethanol does indeed raise the octane number…and the primary reason it is added to standard pump fuel is cost; it also has the added benefit of slightly reducing emissions. If relatively large amounts of ethanol are added, the petroleum-based component of the fuel can be less refined, lower-octane and thus cheaper. From my own experience, if an engine is not optimized to run on E10 it does indeed run worse, probably for the reason I mentioned. I doubt that lower-quality petro fuel is being used in F1 though.gruntguru wrote: ↑18 May 2022, 03:23That's a totally different kettle of fish. Road engines are not tuned to the ragged edge in terms of octane requirement or AFR. They can't be because they have to be durable enough to last several years and hundreds of thousands of km without going out of tune or knocking themselves to death due to carbon deposits. E10 typically raises the octane a few points (good) and leans the mixture about 5% (no problem - especially with lambda sensors).
Yeap it is go to do a reset on the ecu once you switch over in my opiniongruntguru wrote: ↑21 May 2022, 07:45Many engine management systems - going back many years (say 1985) are able to recalibrate the entire fuel map based on variations from the base map detected in areas that are designated lambda 1.0 (eg Delco "Block Learn"). Primarily designed to adapt to deterioration in mechanicals and sensors (particularly in speed-density EM systems) these will also easily correct the entire fuel map for a switch from E0 to E10.