dans79 wrote: ↑01 Jul 2021, 22:18
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Another area I find interesting is the new intake plenum, and the issues they have had with it. I've pondered more than once that this might be somehow related to the move to 10% ethanol next year. If memory serves more ethanol means it can run higher compression ratios.
The compression ratio of a gasoline engine is limited up to 11 to avoid knocking performance and depends strongly on the hydrocarbon type which indicates the antiknock characteristic of a particular fuel. As a rule, high compression ratio engines running high ON fuels provide a higher thermal efficiency. Then a bio-fuel engine can ensure the antiknocking performance, leading to a higher compression ratio, and thus higher thermal efficiency can be obtained.
Biofuel is a mixture of mostly organic wastes, not just ethanol. And unfortunately has many disadvantages had it`s used as a fuel. To start with ICE has worse performance-wise. Then the viscosity index hence lubrication is lower than running usual fuels. Thus, means ICE must run less in anger together with some reliability concerns. Then another headache comes from the combustion chamber, block alloy&stuff and knocking. Practically means a new ICE must be designed from scratch. For this year is just 5.75% biofuel but next year must be 10% and due to cost cap policy, the best route is to develop new oils which should ensure at least 2 important properties: 1. To have a higher viscosity index to compensate for the biofuels effect; 2. To have a higher HTHS “High-Temperature High Share” parameter, just to ensure that ICE it could run longer at the highest mode in races.
