GR86 Premium MPG

[ZDan]

Originally Posted by Dzmitry

True, but I drive a little over an hour to and from work every day. I take the same exact route every time.

In 2018, so did I. Calculated mileage varied quite a bit even driving the same commute with the same driving style every day, roughly +/-2mpg. I think a lot of the up/down/up/down is due to not topping off to exactly the same fuel level every time, even though my topping-off method is exactly the same. There's just too much uppie/downie in it to try something different and expect the difference to fall outside the noise.

But the only comparison within those results that matters to me, is I'll take the fun and enjoyment aspect of the car for the loss of a couple mpg's over driving it like a granny just to save a couple bucks. So it's more of a personal comparison for me, more so than a true statistical one.

Of course you should drive it how you want to! Personally, commuting, it doesn't make much/any difference to me whether I'm short-shifting or not. If there's traffic I'll just try to minimize number of shifts...

[Dzmitry]

Originally Posted by ZDan

Of course you should drive it how you want to! Personally, commuting, it doesn't make much/any difference to me whether I'm short-shifting or not. If there's traffic I'll just try to minimize number of shifts...

Indeed, in traffic, I drive like any rational human should drive. I let all the fools cut me off only to get one car length ahead of me.

[Sasquachulator]

If it matters, i just came back from a 450km (279mile) road trip.
according to the trip computer:
I did 6.3L/100km (about 37mpg)
Mostly 110km/h (68mph) and 120km/h (74mph) on the highway.
its pretty much -10C (14F) and 205/55/16 winter tires.
Not the most accurate relying the on trip computer but hell it cant be that far off.

And its alot better than i was expecting the highway MPG to be (i was expecting to be around 32-33mpg)
(best mpg i ever got was over 40 mpg in a honda fit and 37-38 in a scion iM)

the FA24 should best the EPA ratings easily as well.

[MajorGerth]

Originally Posted by Sasquachulator

If it matters, i just came back from a 450km (279mile) road trip.
according to the trip computer:
I did 6.3L/100km (about 37mpg)
Mostly 110km/h (68mph) and 120km/h (74mph) on the highway.
its pretty much -10C (14F) and 205/55/16 winter tires.
Not the most accurate relying the on trip computer but hell it cant be that far off.

And its alot better than i was expecting the highway MPG to be (i was expecting to be around 32-33mpg)
(best mpg i ever got was over 40 mpg in a honda fit and 37-38 in a scion iM)

the FA24 should best the EPA ratings easily as well.

I just did a couple hundred miles in my '22 with the manual, and I got 33.5 calculated by Fuelly. I think the computer read around 35 mpg. I was doing mostly 55-65 mph, and on long stretches I was switching between 5th and 6th gear to vary the RPM since I'm still in the break-in period.

[mazeroni]

They did a highway loop MPG test at 70 mph in an automatic and they averaged 34 mpg. On summer fuel, maybe it would go up 1-2 MPG. The manual in that same scenario would likely get around 32 due to gearing. It doesn't seem like the car has drastically worse fuel economy than gen I. Improvements to parasitic loss and better front aero probably helps offset the bigger engine. Although I'd wager that if you are really getting on it, you might wind up consuming a tad more fuel just because HP isn't free. The bigger engine means you are dumping in more fuel.

[Lelandjt]

Would you guess that the extra duckbill on the higher trim Toyota adds some aero drag?

[PLF69]

Originally Posted by Lelandjt

Would you guess that the extra duckbill on the higher trim Toyota adds some aero drag?

From the reviews they say its supposed to but I would be curious to know how much and from what speed ?

[Lelandjt]

Originally Posted by PLF69

From the reviews they say its supposed to but I would be curious to know how much and from what speed ?

It'd be funny if it's enough to make a slight difference in top end acceleration. Combined with the bigger wheels hurting acceleration out of a turn and maybe even lowering max corner speed, the lower trim might be measurably faster on a track.

I don't suspect any extra downforce at the very back of the car helps lap times.

[alex87f]

On a track, PS4 vs. Primacy pretty much seals the deal in favor of the higher trim.

Side note: did anyone here ever really notice a difference in "butt dyno" between 91 & 93 on a stock gen. 1?

I've switched back & forth many times, and truly can't see a difference.

[mazeroni]

Originally Posted by alex87f

Side note: did anyone here ever really notice a difference in "butt dyno" between 91 & 93 on a stock gen. 1?

Nope. When I've had to go 87 because of 91/93 not being available either where I was traveling in a rural area, or due to people panicking due to storms or whatever, I have never noticed anything.

If it is a super hot day and you are at the track, maybe 91 would net you a loss of a couple HP, assuming the car detects any pre-detonation. You could probably safely go full 87 if you are just cruising around at 2~4k.

For me, the cost difference between 91 and 93 is like $.30~$40 per gallon, or a few bucks each fill-up. So I just go 93.

[Lelandjt]

Kind of on this topic: Driving between 7,000-11,000ft (mostly 9,000-10,000), temps of 45-75°F, and having 85, 87, 91 octane available. What would you use? On the one hand 85 makes a bigger bang. On the other if this engine computer is capable of adjusting everything to the edge of detonation maybe it can make more power on 91.

[dragoontwo]

Originally Posted by mazeroni

Nope. When I've had to go 87 because of 91/93 not being available either where I was traveling in a rural area, or due to people panicking due to storms or whatever, I have never noticed anything.

If it is a super hot day and you are at the track, maybe 91 would net you a loss of a couple HP, assuming the car detects any pre-detonation. You could probably safely go full 87 if you are just cruising around at 2~4k.

For me, the cost difference between 91 and 93 is like $.30~$40 per gallon, or a few bucks each fill-up. So I just go 93.

I have noticed when moving between 93 in TN and 91 in IA on my tuned 2020. I have also confirmed that the IAM was never 1 when on IA 91. as soon as back on 93 it went back to 1.

[mazeroni]

Originally Posted by Lelandjt

Kind of on this topic: Driving between 7,000-11,000ft (mostly 9,000-10,000), temps of 45-75°F, and having 85, 87, 91 octane available. What would you use? On the one hand 85 makes a bigger bang. On the other if this engine computer is capable of adjusting everything to the edge of detonation maybe it can make more power on 91.

If I'm reading correctly, 85 is the same as 87 at high altitudes. If that is all you have access to, it should be fine. I'm not aware of modern engines being damaged by using lower octane gas. They are smart enough and built well enough that it shouldn't damage anything.

But there are discussions about its impact on fuel economy negating the cost benefit.

Still, I feel like you would probably have to be revving the shit out of the car to maintain speeds going uphill or to pass people at those altitudes, and with so little torque already, I would always use the highest available.

[StormTrooper]

That's not really true with modern engines. Engineering explained does a great video on this on YT.
I would not put anything under 91 in the 86 just to save a few bucks. It probably won't blow up but it'll definitely be pulling timing to save itself.

My first gen was usually around 28-30 mixed but idaho has a lot of open roads. My gs350 awd gets horrid ,damn near sti mileage no matter how easy I drive the thing.