MPG expectations? FR-S and BRZ

[Brody8877]

EPA rating on a rsx type S is 23city/31hwy

Don't forget to factor in driving habits/ elevations/ and road conditions.

When I had my 07 WRX Wagon (stock) I got like 14mpg on city in SF, and 21/24 hwy. While the EPA rating is 20/27. BTW I drive like grandma and did my best to stay off boost on the hills of SF. On my rsx-s I get 20-21in the city and if I do all hwy I get like 33+mpg. It'll be great if the FR-S/BRZ gets like 25+mpg on mix driving conditions because I would consider trading in my RSX-s for it

[Mino]

Originally Posted by Brody8877

EPA rating on a rsx type S is 23city/31hwy

Don't forget to factor in driving habits/ elevations/ and road conditions.

When I had my 07 WRX Wagon (stock) I got like 14mpg on city in SF, and 21/24 hwy. While the EPA rating is 20/27. BTW I drive like grandma and did my best to stay off boost on the hills of SF. On my rsx-s I get 20-21in the city and if I do all hwy I get like 33+mpg. It'll be great if the FR-S/BRZ gets like 25+mpg on mix driving conditions because I would consider trading in my RSX-s for it

That's what I was hoping I'm thinking about trading in my G35 and I avrage about 20MPGs mixed. My 06 integra with a type-r engine I use to get 24mpg but I was young and drove like an idiot most of the time lol

[iff2mastamatt]

Anyone else notice that this car requires premium?

[Dave-ROR]

Originally Posted by iff2mastamatt

Anyone else notice that this car requires premium?

Suggests.. It'll retard timing like all modern cars if you run less.. you'll just have less performance and fuel economy (and some say potential damage).

The loss of economy offsets the difference in gas prices.

[miata]

The sixth gear should be a true overdrive gear. That way it will cruise 60 mph at 2000 rpm.
If you need to pass what's wrong with downshifting? Shifting is fun, right?
They can do the close gearing ratios all they want 1st thru 5th. At the race track who shifts to 6th gear anyway?
If I can cruise at 2000 rpm on freeway I will be a happy camper.

[serialk11r]

Hmmm I haven't ran any calculations and I'm bored so let's test your 2000rpm @ 60mph cruise gear out on paper:
Someone calculated a Honda Insight to require 17hp at 60mph or so. The FRS weighs about 50% more, and has similar aerodynamic drag. The extra 400kg amounts to about 40N more force required for rolling, and 60mph is 1600m/60s which is about 27m/s, so the power required is about 1.1kW, not much of a difference. Let's just say it'll need 20hp.

At 2000rpm we likely have about 25% of total power available. So 50hp. Through the drivetrain this turns into a hair over 40. Most BSFC charts of throttle plate controlled engines indicate the at about 50% specific torque efficiency is within 10% of peak. The extra ~15hp (don't want to go wide open throttle) would be enough to travel up a 10% grade. Sounds pretty good I guess if you're at higher altitudes you lose some power so maybe 2250ish would be better, which also allows for slightly higher speed hill climbing.

Anyone remember if the 2500@60 was accurate at all? In the gearing thread OP said 75 seems like around 3100 (although this could be lower) so 60 would be more like 2400-2500. If it's lower than that mpgs should actually be really really great at 60-70mph, since the engine would be running so close to peak efficiency, maybe even 50mpg would be possible :O If an Insight can cruise at >60mpg, this can do 50 if it's operating only 10% away from peak efficiency (expecting the Insight to have slightly better efficiency built in). Well I guess that is another reason why Valvematic is missing. I guess it's not necessary until mandated mpg goes past 40.

[Levi]

I don't care about MPG as it will definitely be better than my current Alfa Romeo and will also be better than most turboed cars when pushed hard. A turbo is horrible driven like stolen.

[Sasquachulator]

As long as its at least equal or close to my car, im cool with it. I think its rated t 26/34 or something. (2zz-ge)
Im kind of expecting the EPA to be similar to that of the current tC (23/31)

Premium gas doesnt bother me, my car needs it anyways lol.

[serialk11r]

Well now that gear ratios are out...
It appears that we have ~2350 rpm @ 60mph on the 3.7xx differential. That's somewhat low, but there's still quite a lot of excess torque. Looking at some BSFC maps, we can expect this to be somewhere around 270-300g/kWh (taking into account direct injection, high compression, it's likely closer to 270, given how peak BSFC on the 2GR-FSE is nearly the same as that on a 1NZ-FXE). A Prius cruises at about 240g/kWh efficiency, but is slightly bigger than this car, I think they typically can cruise at mid 50s to 60+ if you consciously optimize load. Worst case 300, still pulling a strong >42 mpg at 60mph .

This seems pretty high but if you think about how short Civic Si (2.0L) were geared, and the fact that they could almost hit 40, then 40mpg should be a piece of cake in this car.

[carbonBLUE]

yeah and fuel trims also matter, my car gets these mpgs

60mph - 34mpgs
70mph - 29mpgs
85-95 mph i get 31 mpgs... lol

i dont know why it gets better after 70, but i dont complain cruising long distances at 100 getting 30 mpgs...

i can make a 12 hour trip in about 8 in a half only having to fuel up once and have enough time to eat subay getting about the same mpgs as if i were to cruise around 65...

i wonder if any 2zz-ge owners have experienced the same thing?

[tranzformer]

Originally Posted by carbonBLUE

yeah and fuel trims also matter, my car gets these mpgs

60mph - 34mpgs
70mph - 29mpgs
85-95 mph i get 31 mpgs... lol

i dont know why it gets better after 70, but i dont complain cruising long distances at 100 getting 30 mpgs...

i can make a 12 hour trip in about 8 in a half only having to fuel up once and have enough time to eat subay getting about the same mpgs as if i were to cruise around 65...

i wonder if any 2zz-ge owners have experienced the same thing?

That is interesting. Is your car stock?

[ryude]

My GTI does the same thing.

65MPH = 36MPG
70MPH = 32MPG
80-85MPH = 35MPG

Of course I don't average that, city MPG is in the teens for the GTI. I don't care what the damn EPA rates it at, I've never averaged over 27MPG.

[tranzformer]

Are you guys basing those mpg's per mph off the computer estimated mpg or are you manually calculating it?

[ryude]

Originally Posted by tranzformer

Are you guys basing those mpg's per mph off the computer estimated mpg or are you manually calculating it?

I have a scangauge. It reads about 2-3 MPG less than the onboard instant/average MPG. The GTI has a Direct Injected 2.0, when you're cruising around 50-55MPH it will get 50MPG easy. That's why I know the BRZ will get at least 30-32MPG average.