I don’t know what, if anything, changed from 2015 to 2016. They may have altered the code related to ignition or injection timing to allow for 87 to be used more safely. VW used premium for hp rating because you’ll get more power out of premium. If it were my car, I’d probably use 91 octane unless I was on a cruising road trip, and then I might buy 87 or 89 octane.
87 is good enough for me, unless I’m in high altitudes then 86 is good enough for me.
Yeah, in Denver 85 octane is regular unleaded. Higher altitude, less dense air, lower cylinder pressure and less knock. But premium is still 91 octane.
That reminds me, when I had my Mazdaspeed3, I had an issue that turned out to be a fuel pump. But it was hard to diagnose, so they put me in touch with the Mazdaspeed engineers. They told me at my altitude, 89 octane would be fine (the spec was 91 I believe).
That’s what I figured, was going to look that up today. I think I’m going to start doing 5 over instead of 9 over.
79^2 = 6,241 (assume 35.0mpg)
74^2 = 5,476 (implies 12.3% less drag, 14.0% higher fuel economy => 39.9mpg)
70^2 = 4,900 (implies 21.5% less drag, 27.4% higher fuel economy => 44.6mpg)
My car is a 1.5L turbo which according to the specifications gets better gas mileage than the 2.0L non turbo. Not sure exactly why that is, apart from 25% less cylinder weight.
I recently took a long trip in my car and noticed that I was in higher elevation in Amarillo (3,600ft) and opted not to put the 85.5 octane gas in my new car. I figured it was because of the elevation, but I was also leaving Amarillo and a couple hours later Wichita Falls was elevation only 950ft…
Not sure what you’re driving, but those numbers look about the same for my car (Lexus CT 200h, a fancyman’s Prius). Also, net downhill will also increase mileage. We’ll drive to the beach from 1000ft elevation, get great mileage, but coming back, it’s worse. Now, I know in Iowa, this is not relevant, but drive to Colorado and then back, you’ll see a big difference as well.
Ah. Nice!
The whole 55 mph speed limit in the 70s was about reducing fuel consumption due to the oil crisis…
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Extrapolating this to 55mph makes that mileage improvement for drag seem like it’s probably too steep.
I am not old enough to have been driving when 55 first became the national maximum speed limit, but am old enough to have experienced it. The main rationale for implementation was improved fuel efficiency (1970’s fuel spike prompted the action), but the actual savings were less than expected.
Probably because they “expected” people to actually drive 55. But in many places you wouldn’t get ticketed under 70* because the state and the cops enforcing the law thought 55 was bullshit.
*Unless the cops suspected you of something else like having drugs in the car, or they felt like messing with you or had been instructed to raise revenue for their jurisdiction.
There is also friction, which varies linearly with speed. So it’s not quite as simple as squaring speed and taking the difference, but drag starts to become a huge deal when you’re talking 70mph.
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I too, own a vehicle with a 1.5L turbo (Honda CR-V)
What is amazing to me is the power that is generated from small engines, compared to engines of yesteryear. When I was in high school, Ford reintroduced a 5.0liter V8 that made 200 HP, and it was considered a monster engine. That’s 40HP per liter. Now my little 4 banger econobox Honda gets nearly the same HP (190) as that out of a motorcycle sized engine at 126 HP per liter.
Yeah, the whole ‘there’s no replacement for displacement’ thing. Turns out there is: boost.
I still remember when Subaru brought the WRX STi stateside, and Hot Rod magazine put it on the cover. Next to a blown 5.4l V8 Mustang Cobra. The Subaru spanked it on a road course, and beat the Ford by 0.01s in the quarter mile, call that a draw.
Mercedes has a 2.0l that puts out 421hp. That was super car territory for me growing up.
My first vehicle around high school time was a 1987 Dodge Omni. It was 2.2L and generated 96HP, or 43.6HP/L. My current car is 180HP/1.5L=120 HP/L almost triple.
The scare for me is longevity. Is that 2.0 liter going to ping itself to death at 50k miles?
Depends on how you drive it and maintain it.
Yay I made the list!
I have not tested that 0-100 MPH meter - who drives 100 MPH?!
It does seem worrying, but it comes with a warranty. The prior version had 355hp and seems to have held up well. I’d like to see analysis of the used engine oil to see what wear metals are coming out of these things.
I did look at some oil analysis on the Civic Type R, 2.0l and 306hp, and it looked good, even on cars with track time. The K-series engines seem to be about as reliable as a wood burning stove, even with 23psi in the manifold.
“We always assumed that mid-grade fuel existed chiefly to bilk a few more dimes from the type of people who ask the dealer to undercoat their car. Turns out it’s also for owners of Fiat Chrysler’s Hemi 5.7-liter V-8, as the company recommends 89-octane fuel for this engine. With no mention of that on the fuel-filler door, though, a driver would have to read the manual to know.”
TIL.
I do. On very rare occasions. Mainly, to see how my car sounds at that speed.
So does @Triweasel, to my utter fright.
My first car had a speedometer that went only up to 85 (to discourage high speeds), but when pinned it was about 100 (lots of space between 85 and the pin).
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