gman

3000-3500 and keep it running around 2000-2500

Highway was strictly highway, all cruise control for about the full tank, ~58 mph

I know, no fun at all. But until break-in (~50 more miles), I'm treating it like a baby. Then forget about Gas Mileage. I won't care.

Hercules

Hi all. Given that my first tank yielded 14mpg, the second 14.5 and my third 15mpg... I felt given the EPA estimates I should get better. It didn't matter much to me really, but it was a goal to increase my gas mileage.

First let me state the facts: my last tank of gas yielded me 20.2mpg (secrets to follow). I drive almost religiously with the windows rolled DOWN, and air conditioning off. I have a heavy foot and tend when I'm in my 'element' to reach that 9000RPM.

First, let me state this to those people who love driving with the windows open (me!). POP THE REAR WINDOWS OUT. After doing my homework on the internet, I found that your gas mileage is decreased by 25% if your front windows and not rear windows are open, causing excessive drag on the car. By popping the rear windows, you will get a breeze thru your car, no 'buffeting' (that wonderful sound that envelops the car at speed), and the drag on your car will be greatly reduced. This is probably the #1 tip I can give for gas mileage saving.

Secondly, use awkward shifts! What do I mean? Well, I have a habit of rowing the gearbox very quickly since my lead foot helps me climb the tach and gearbox in a rapid manner. I found that when I'm going 40mph, I will shift from 3rd right to 6th and cruise. Given that almost ALL of my driving is city, I found this to be a great stress reducer on the engine as it rides at around 2k rpms very smoothly and without the sputtering that you'd expect if you were in too high a gear for the given speed. There are drawbacks to this of course, mainly that there is almost *no* power using this method. But if I'm driving along a city road (which I often am) I don't really see any need for the power a lower gear would yield and the decreased exhaust note is an added benefit as well, making the stereo a tad better to listen to

Lastly, drive on WELL PAVED ROADS. Another huge negative on driving on uneven roads is severely decreased gas mileage.

So simply put.. pop your rear windows, skip gear and go right to the high gears, and find even paved surfaces to drive on.

If you do mixed highway and city driving, you should yield over 20mpg, and if you do all city... right in the neighborhood of 18-20mpg.

Good luck, hope this helps some of you!

B-Nez

Dude, thank you for this. I have tried both windows open AND A/C, also windows open in town, A/C on highway with sunroof cracked to vent drag (hopefully anyway), and I'm still around 17 mpg. The rear windows I hadn't even thought of. I will definitely try this outafter I tank up (accidentally reset my trip meter doing the diagnostic mode...).

As for the skipping gears, I have been doing the same thing. I jam to the tune of 9000 when accelerating, passing, whatever - but once I get to my target speed I shift into whatever gear will let me cruise between 2-3K.

Racer X-8

I dunno how much it helps, but I've gotten into kind of a habit of coasting a lot lately, not as much with this car, as with my (lame anyway) Infiniti G20T. It's amazing how far you can coast, like downhill (duh!), or through a couple blocks of suburbia. Try it a little.:D You can go for 1/2 mile or so & in some instances, only loose some 5 mph by the time you get to that stop sign or light up ahead. Aw, go on & try it!

A 6s Owner

I'm sure other RX-8 owners will thank you for those tips.

As for me, I think this is just terrible. These "tips" sound like major sacrifices (inconveniences is a better word) to my ears, especially since I don't own an RX-8 yet. For people that live in the warmer regions of the country (such as myself), driving with air conditiong off and with opened windows IS a living hell (especially right now in the summer).

Racer X-8

I think you've read too much into these posts a little maybe.

Nobody said to turn off your AC. Although that would help, that goes for any car. Herc & B-Nez were discussing the reduction of aerodynamic drag when you want to have your front windows open. That's got really nothing to do directly with deciding on AC .vs. open windows. It's about reducing drag when you want to open your windows.
Major sources have determined that AC uses less fuel than open windows anyway.

My tidbit about coasting is really universal to all manual transmission auto's. Like I said, I'm doing it a lot lately with my 29.5 mpg Infiniti G20T. I haven't been doing it as much with the RX-8 actually. I dunno why that, really.

OK?

TJRX8

I'll have to try that around January when it gets cool enough to drive with the A/C off and windows open. :D

As for the shifting, I have been doing that as well on ocassion. I try to use the Cruise when ever possible. That is supposed to help also.

Instead of coasting Racer, I'm going to cut a couple holes in the floor Flinstone style

PoLaK

iTrader: (1)

I don't know how many other people do this but I throw the car into neutral whenever coming to a stop sign or a red-light. It adds up after a while.

Quick_lude

While coasting in certain situations might help you save a bit of fuel, it's generally not recommended. You should always be in gear, I believe you will fail a driving test if you coast in neutral.

Napboy

I had never considered this but 25% reduced drag sounds like a lot for having your back windows cracked. If it's true, that's awesome.

Also I noticed how driving with your windows open in the 8 doesn't create the "wind tunnel" effect that other cars do. Keeps my hair becoming wind-blown before work.

Racer X-8

Cheeez, really? Well, shucks! Next time I take a driving test, I'll try to remember that lil' gem of knowledge.:p

Quick_lude

I'm assuming that's sarcasm.. You'd be surprised how many people don't know that on a driving test you always have to be in gear. I know they used to fail people for this.. not sure if they still do.

akrx8

thanks herc,ive tried just skiping gears to cruise in 6th around town and looks like i will top 245 miles from 13.4 gal on the 3rd tank.18.1 mpg is pretty good for the playing i like to do and idleing forever at lights.once i really try i think i can get 22 or 23 if i can cut down on the playing.:D

Elak

The relatively higher fuel prices in Europe have yielded research results that are frequently published in magazines and newspapers (usually during the news dry spell in summer). Appart from the obvious (avoid using AC etc) there are two that are worth mentioning:

#1 accelerate rapidly to crusing speed, rather than slowy inching your way up to speed (within limits of course).

#2 Try to regenerate energy by engine breaking rather than pedal breaking. While engine breaking the fuel injection is shut off (at least modern piston engines, but I don't see why the Renesis wouldn't). This means that instead of expensive gas being used to spin the engine (generator etc) the wheels do the job. For this reason coasting in neutral is not recommended.

/Elak

PoLaK

iTrader: (1)

Well I'm Taking the road test in an auto, not that i wouldn't do it with a stick, i just don't think i could because they don't allow u to have a raised center console between the driver and the instructor. And the is no harm in shifting into neutral when coming to a stop saves your clutch too. Nor is it unsafe by any standard.

mantisflie

In California, it is illegal to coast in neutral. Or so I was told by a CHP after I came down the 4 lane in the Sierra foothills in neutral. Didn't realize how inefficient the front windows were on gas! Will try the back window thing. He he, no problem here with accelerating to "legal" speed quickly. :D

norats

How in the world did the cop know you were not in gear? I can't imagine he could hear your car's engine over the road noise & sounds of other vehicles...???

jimbobjoe

The problem with coasting is that you don't have full control of the vehicle anymore. If something jumped out on you and you have to swerve and possibly hit the gas, you can't.

In pre-ABS days you have a much higher chance of locking up the wheels if you have to hit the brakes.

In the UK I don't think there is a specific rule banning coasting (how would they really tell?), but you are expected to be in full control of the vehicle at all times.

Lock & Load

Realistically apart from not using the A/C the only other way is using appropiate gears and getting up to 6th gear ASAP , what i have trouble in understanding why buy this type of car expect to work the gears try for 6.2 to 100 km and then worry about petrol , it does not compute , the difference in your saving may be an average of $ 20 per wk the difference between shear boredom or great fun .

Enjoy the car and dont get paranoid about the petrol cost
, if you cannot afford the petrol you should not have brought the rx8.

B-Nez

Yes, that is true to a point. I have not been terribly concerned with my fuel consumtion as others in other threads have been, but it is more of a curiosity for me. I noticed I've been a little on the low side, and have been experimenting a little bit. I still do plenty of buzzer shifts when not floating in traffic, and have loads of fun in the corners. I'm sure my wife would smile a little bigger if I walked in and said, "I got 20 mpg this tank" rather than, "I did an awesome reverse 180 today..."

Wing

Accelerate quickly? That seems VERY contradictory, I have read numerous times it is better to have less acceleration than more. But what the heck do I know ??

rx8daniel

as an experiment, I drove mostly at posted limits (60-65) last night and today and managed 22mpg; will try again over weekend around 60. I think two largest contributors to lower MPG are quick acceleration and high cruising speeds. At 55MPH constant speed an RX-8 may be capable of nearly 30MPG, but unless one were to install a meter on their car we may never know. I'll try this weekend a R/T around 55MPH from the convenience store where I work P/T and back and see what I get!

wakeech

...there are arguements that slow acceleration (because it takes more time) is less efficient as dragging losses act on the car up to speed for longer.

there must be a "most efficient" way to accelerate, which is probably fairly brisk, but i'm not so sure about going WOT from every stop sign and pegging it at 40mph (wouldn't that be a 1 - 6 or a 1 - 2 - 6 shift??)

wakeech

...ok, there's an old thread here (which i know no one bothers to read 'cause they're closest to the end of the lists you get when you pull up a search) which discusses fuel consumption and efficiency in great detail... it's really a gem (Buger, Grimace contributing very major points... i was in there too a little), so look it up.

in any case, the optimal fuel-saving situation at cruise is being in the highest gear, at as low a speed as you can go. at 50 mph in 6th, your rpm's will still be at a very acceptable 2500 with low aero-drag and rolling losses: you just won't get anywhere very fast. FWIW, i observe this same condition in my car; 70kph is the shift point from 3rd to 4th for the auto tranny (with normal throttle) and is right where i find the best fuel economy, so if i'm really pressed for bucks to put in the car (laugh if you want :p) i'll speed in the residential areas (by like 7mph :p) and go under the speed limit on the rural highways.

Skyline Maniac

Realisticly people don't turn off AC just to save gas milage. Skipping gears is a good idea though. If you want optimal gas milage, remove all the junk and spare/jack in your trunk to reduce wait, fill up gas only half way to reduce fuel load, and close all windows to reduce drag. If that's still not enough, then it's time to buy a brick and stick it under the gas paddle. Shift at 5000rpm and forget about performance.

Honestly guys, the RX-8 is a performance oriented car, and performance doesn't always equal good gas milage. Rotary in particular is known for needing lots of fuel and oil. Use the 6th gear as often as you can, the RX-8 has a really tall 6th gear that's designed to yield the advertised milage. Finally, if you are on the highway, use the cruise control and don't drive too fast. You waste around 15% fuel for every 10mph you drive above posted speed limit. (on an average car with higher .CD)

On a side note, I am getting pretty sad milage in my G35C, but then again I drive 90% city in stop and go traffic and my car sits idle all the time, so I can't really complain.