Delphi wrote: ↑Mon Sep 06, 2021 12:47 pm
Beany wrote: ↑Mon Sep 06, 2021 12:25 pm
It's a non issue till they mandate that super had to be E10, too.
It's it a mapping issue, or just fuel pipes that need replacing?
The octane rating is the same, so no mapping changes. It's the pipes that rot and the tank as well.
Actually that's not strictly true. Whilst I imagine 99.9% of cars will cope absolutely fine and you'll barely notice the difference, diluting petrol with 10% ethanol actually lowers its stoichiometric ratio to about 14:1 from 14.7:1 if it were 100% gasoline. Most cars are trundling about for the majority of the time with the engine management making sure that the mixture is running at 14.7:1 (or Lambda 1 for 100% petrol) which means with E10 you're actually running a tiny bit too lean, which will result in hotter temperatures in the combustion chamber. Given that its less calorific you'll also lose a tiny bit of mpg too.
Likewise, modern performance cars tend to run so rich at WOT that it won't hurt them running E10, but if you were doing the job properly you'd map a car for the fuel its running on.
I've mapped cars on E85 and they need to be running AFR's around 9:1. If you tried that with petrol you'd just put the fire out