4 ms·

The "best" figures for a petrol car is 39mpg, which seems a bit low. My (diesel) car will do over 50, and it's over 10 years old and isn't famously economical.

62951413 4y ago
It's not unusual for my 2-year old Elantra on my 48-mile commute to San Jose down 680 to reach 50 MPG. 47 for going back. I do drive earlier/later in the day to avoid the rush hour.
lotsofpulp 4y ago
Petrol is not diesel, so not sure how your datapoint relates. Which petrol cars get more than 39mpg? Also, were diesel cars only getting those high mpg due to cheating the emissions limits? I never saw them in the US.
- ghusto 4y ago
  > Also, were diesel cars only getting those high mpg due to cheating the emissions limits? I never saw them in the US. I don't believe so. Diesel is more efficient partially because diesel engines have been around longer (so have more improvements).
  - sokoloff 4y ago
    They have a much higher compression ratio and also aren’t pumping across a partially closed throttle plate virtually all of the time.
- adhesive_wombat 4y ago
  My car gets over 50 mpg and that's from odometer and fuel volume, not from a spec sheet. Diesel goes a bit further than petrol on a volume basis but not that much. Maybe it's just due to smaller US gallons and a cruisy commute. A colleague of mine gets 65 mpg, fwiw, and it's not a hybrid. Also the emissions thing wasn't about fuel economy, but about NOx emissions.
- prmoustache 4y ago
  > Also, were diesel cars only getting those high mpg due to cheating the emissions limits? I never saw them in the US. Because you guys like huge heavy cars full of unnecessary toys inside.
- Rebelgecko 4y ago
  Lots of hybrid sedans, eg Prius, Corolla, Ioniq, Insight Granted I think the only non-hybrid ICE getting 39mpg or better is the Mitsubishi Mirage.
saltcured 4y ago
Your use of the word "petrol" makes me wonder if you are aware of the difference between US gallons and UK/imperial gallons. UK gallons are larger volume and so give a higher MPG metric for the same vehicle. There also are not many sub-compact cars marketed in the US, and the range of engine options is usually limited compared to similar vehicles marketed in Europe and the UK. Compacts like a Civic or Corolla would be considered efficient commuter vehicles by most people here, and might get around 40 MPG (US) in highway cruising and somewhere in the 30s as a combined figure (for non-hybrids).

62951413 4y ago

It's not unusual for my 2-year old Elantra on my 48-mile commute to San Jose down 680 to reach 50 MPG. 47 for going back. I do drive earlier/later in the day to avoid the rush hour.

lotsofpulp 4y ago

Petrol is not diesel, so not sure how your datapoint relates. Which petrol cars get more than 39mpg? Also, were diesel cars only getting those high mpg due to cheating the emissions limits? I never saw them in the US.

ghusto 4y ago
> Also, were diesel cars only getting those high mpg due to cheating the emissions limits? I never saw them in the US. I don't believe so. Diesel is more efficient partially because diesel engines have been around longer (so have more improvements).
- sokoloff 4y ago
  They have a much higher compression ratio and also aren’t pumping across a partially closed throttle plate virtually all of the time.
adhesive_wombat 4y ago
My car gets over 50 mpg and that's from odometer and fuel volume, not from a spec sheet. Diesel goes a bit further than petrol on a volume basis but not that much. Maybe it's just due to smaller US gallons and a cruisy commute. A colleague of mine gets 65 mpg, fwiw, and it's not a hybrid. Also the emissions thing wasn't about fuel economy, but about NOx emissions.
prmoustache 4y ago
> Also, were diesel cars only getting those high mpg due to cheating the emissions limits? I never saw them in the US. Because you guys like huge heavy cars full of unnecessary toys inside.
Rebelgecko 4y ago
Lots of hybrid sedans, eg Prius, Corolla, Ioniq, Insight Granted I think the only non-hybrid ICE getting 39mpg or better is the Mitsubishi Mirage.

saltcured 4y ago

Your use of the word "petrol" makes me wonder if you are aware of the difference between US gallons and UK/imperial gallons. UK gallons are larger volume and so give a higher MPG metric for the same vehicle. There also are not many sub-compact cars marketed in the US, and the range of engine options is usually limited compared to similar vehicles marketed in Europe and the UK. Compacts like a Civic or Corolla would be considered efficient commuter vehicles by most people here, and might get around 40 MPG (US) in highway cruising and somewhere in the 30s as a combined figure (for non-hybrids).