Low Fly'n 8

Personally, I never shift into 6th gear unless I'm on the open road running around 70 mph. I try to stay in the 3,000 to 3,250 rpm range when cruising secondary roads, etc. This engine is happiest when revving. It is not always like driving a conventional piston car. Due to lack of torque, the computer will dump extra fuel to try to compensate when bogging around at 2,300 rpm in 6th gear if you accelerate at all. I have right at 20,000 miles and always get around 18.5 mpg (50 / 50) regardless of driving style. This was discussed in depth when I first started reading this forum and has stuck with me. It works for me.

HD

salituro64

Since the N flash I have gotten 18-20 avg. Doesn't matter whether I baby it or get on it. The only difference I see is hywy vs. city.

I was getting 16-18 before w/ I believe the buggy M flash.

howardteets

Gas mileage in by opinion has not been too bad with this car. The lowest I got was 16.5mpg (Hard Driving), The highest was 20.5mpg (Tried to drive easy the whole tank but couldn't resist opening it up a couple of times). I pretty much do everything in the original post with a couple exceptions.

Scenario: Cruising at ~55-60mph in 6th gear, want to accelerate to pass / change lanes.
Shifting: Downshift to 4th get to desired speed, shift back to 6th.

I don't know if this is what a lot of you are doing and I don't know if my thinking for doing this is right. But wouldn't accelerating in 6th gear actually use more fuel than downshifting to a lower gear. High throttle position inputs in a high gear will make the engine work hard. In the lower gears the engine does not have to work as hard due to the gearing of the tranny. Isn't this the whole point of the transmission anyways?

My thinking: Putting the pedal to the floor in 6th at 55mph will use more fuel than briefly downshifting to 4th to accelerate to desired speed. (It's quicker too)

herbert

I've stopped tracking gas mileage. It wasn't easy for me to do. I do not reset the trip meter. I do not try to register in my brain what the odometer or trip meter shows when I fill up. I know have no idea how many miles/kms I get per tank. I'm enjoying the car much, much better !! I'll probably start tracking again in another 10,000 miles or so (and probably just for a few thousand miles) just to make sure everything's still ok.

spork

Scenario: Cruising at ~55-60mph in 6th gear, want to accelerate to pass / change lanes.
Shifting: Downshift to 4th get to desired speed, shift back to 6th.
Oh, I downshift if I need to pass. If I'm going 45 in 6th, it's really hard to pass people. I'm just saying that if you don't need to accelerate quickly, get into 6th and stay in 6th ASAP. It worked very well for me. Tt was either that or the coasting in gear, or both which helped bring my mpg up rom 16-18.

I don't think it's that bad to go to higher rpms, provided the bulk of your time is in 6th gear and below 3.75k rpm.

I try to stay in the 3,000 to 3,250 rpm range when cruising secondary roads, etc.
Doing the keeping the rpm between 3-3.25 is pretty difficult. It's really easy to be above/below that unless there's no lights and the streets are empty. I tried keeping it between 3-3.75 before and my mileage still stayed around 16mpg.

but wouldn't accelerating in 6th gear actually use more fuel than downshifting to a lower gear.
i'm not sure, but i don't think it would. not positive though so if someone really knows the answer to this, it'd be nice to know the answer.

I just filled her up, went from 12.25 to 13.8. I'll be driving to Matagorda Bay and back in the next few days so hopefully I can see what 6th gear will yield.
If you don't get at least 19mpg on a trip where it really is 80%+ in 6th gear without varying your speed too much (and usually under 74mph), then there is something wrong with your car. There's not much "wrong" you can do driving once you're in 6th gear and cruising where as there can be a lot wrong when you're driving city streets. But then again I don't know if they'll do anything about it. A member here, Howard, got the same mileage as you and he eventually took it in to the dealer and had them test the mileage and they got the same as him (~12). I don't think they did anything for him yet though.

DreamWarrior

I do everything in this thread, for the most part, and I average 19 MPG. Most of my driving is to/from work and is about 60/40 c/h. This last tank was 19.2 and it was mostly highway, except I was toying around for some time and above 100MPH for a while.

My typical shifts leaving lights are either 1-2-5 (for speed limits 35-40) or 1-2-6 (for higher speed limits). Out of my 1-2 shifts, I'd say 85% are at 5-6k. 10% are above 6k and the last 5% are under and only done when the speed limit is really slow. Furthermore, most of my 2-6 shifts on high speed roads are in the 5-6k range or higher too.

I dunno, the way I look at it, the faster I can get to a coasting speed, the less overall gas I use. And, given my 19MPG average, I guess I'm not too far off.

edit: my highway cruising speed (as per the speedo) is generally 75 if I can do it with the surrounding traffic (which is often).

ferragame

Haven't done the calculation but it is much worse than my previous car ('01 BMW 530i). I have a 40-45 mile commute to work each way. Currently spending about $12 a day for fuel ($2.00 to $2.30 a gallon for premium). I figure I'm using about $60 a week. I was using about $40 - 45 a week with the BMW.

BUT, I don't care. I knew the car got crap fuel mileage. I think even my '05 X5's mileage is better. I bought the car for fun so I'll just have to live with the fuel cost. If fuel hits $4 a gallon, maybe I'll buy another BMW or Audi to commute with and keep the 8 for fun. Until then, I'm having a ball with the new toy.

MeToo

I coast in neutral clutch out ... Do I save just as much as coasting with it in gear?

Shinka13

I averaged about 21.5 on the highway, cruise set at 80mph. In town, I have been averaging about 19-20 mpg. This is with a 6mt and very varying driving habits.

dazygirl415

^^ about the same here. I got tired of tracking mpg stats and figured I'll have to fill up regardless anyway so why bother? And most of my driving is city and very little, IMO, can be done to help me there.

LiveBlues

Those are great tips, but I think it also goes to show how unique our cars are. Last Friday, I filled up and then took a trip up the highway running about 75-80 mph and passing a few cars along the way. I was following a friend in a Cavalier btw. He drove the crap out of that car. Then we started up a twisty mountain pass, going from about 6000' to 8800', running high revs and driving hard all the way up and back down. Then we opened it up for the duration of the trip, running about 85 and passing cars, hit a high of 96 for a brief period of time. The trip back home was much the same, but probably not quite as fast. Round trip was probably about 175 miles. Then I drove the rest of the week back and forth to work as usual. I just filled up again today (the fuel light came on). I had 289 miles on the trip meter, and it took 13.9 gallons. 289/13.9 = 20.79 mpg. I haven't had the opportunity to run a full tank of gas on a freeway, but I suspect that I would get somewhere in the 23-24 mpg range. I feel for those that are getting crappy mileage.

gusmahler

If I wanted to follow the tips on the first page, I wouldn't have bought an RX-8.

6th gear at 45? I'm usually in 3rd. Shift at 3k? When I short shift, it's at 4k. Regular shifts are at 6k or above. With the occassional redline shift also. What's the point of buying an RX-8 if you aren't going to DRIVE it.

I figure it's worth the 1-2 mpg to have fun in the car.