You may want to measure fuel economy and power on different octane ratings if you have a modern car. Newer ECUs can advance or retard spark on the fly.
But also:
laughs in diesel
I don’t even need an exact air to fuel ratio. Fuel gets injected as it’s being burned not before.
(let’s ignore the fact that I only get 7l/100km or 35 mpg which is super inefficient for a diesel, because it’s a heavy wagon with torsen based permanent AWD and an older 1600 bar common rail system)
It’s my understanding that diesels get more efficient the more load they’re under… The extra weight actually makes them burn cleaner and more thoroughly.
To be fair, yes, the weight might not even have THAT much to do with it. The funny thing is, my car is over 1800 kg. It’s an Audi A6 wagon. The SQ7 TDI which has tons more power and torque in a much heavier car, is more efficient. It just sprays the fuel quite differently and does a ton of other magic.
But the real thing isn’t that weight makes them more efficient, it’s more that they have so much torque that towing a heavy load doesn’t affect them nearly as much as a petrol engine. For more efficiency these days we have VNT turbos so you don’t need a ton of load to get boost (and thus a bunch of extra air). The cool thing is that you can add any amount of air, diesels run hot when rich, not when lean. So you can go for like 30:1 AFR for efficiency. Hell you could go 200:1 AFR in some circumstances (when fuelling is pulled due to letting off the pedal, but boost doesn’t get reduced as quickly)
Use the lowest octane that doesn’t cause pinging or knocking. The ONLY thing premium about gas is the steability at higher pressures…
93 octane doesn’t self-ignite as easily, and in higher compression engines this matters…
You may want to measure fuel economy and power on different octane ratings if you have a modern car. Newer ECUs can advance or retard spark on the fly.
But also:
laughs in diesel
I don’t even need an exact air to fuel ratio. Fuel gets injected as it’s being burned not before.
(let’s ignore the fact that I only get 7l/100km or 35 mpg which is super inefficient for a diesel, because it’s a heavy wagon with torsen based permanent AWD and an older 1600 bar common rail system)
It’s my understanding that diesels get more efficient the more load they’re under… The extra weight actually makes them burn cleaner and more thoroughly.
To be fair, yes, the weight might not even have THAT much to do with it. The funny thing is, my car is over 1800 kg. It’s an Audi A6 wagon. The SQ7 TDI which has tons more power and torque in a much heavier car, is more efficient. It just sprays the fuel quite differently and does a ton of other magic.
But the real thing isn’t that weight makes them more efficient, it’s more that they have so much torque that towing a heavy load doesn’t affect them nearly as much as a petrol engine. For more efficiency these days we have VNT turbos so you don’t need a ton of load to get boost (and thus a bunch of extra air). The cool thing is that you can add any amount of air, diesels run hot when rich, not when lean. So you can go for like 30:1 AFR for efficiency. Hell you could go 200:1 AFR in some circumstances (when fuelling is pulled due to letting off the pedal, but boost doesn’t get reduced as quickly)
Whatever…Diesels pollute shit into the air.
Newsflash: all combustion vehicles do that