Wert4580

1. Praise

I absolutely love my car. Today my friend and I, in 128i and RX-8, respectively, decided to go canyon hunting in Malibu. The end result was a smashing success. Despite almost running into an Astro Van and a Prius on Latigo Canyon, and doing some weird spin-into-understeer manuever on Mulholland, I felt in control of my car the entire time, never slipping out of control (I use DSC - sliding off a cliff is not how I wanna die), always acting predictably, and was able to build up pretty decent speed. My biggest problem was not being able to keep my revs near 5-6k while downshifting; Agency underdrive and ACT flywheel call for some very fast heel-toe action, which I am not able to do. The point of all this rant is I felt very able at the wheel, despite being a total noob, in my first canyon run, on nearly-worn rear tires. Thank you Mazda. Anyone who discredits the RX-8 based on its lack of straight-line power should try what I did today. On top of all this, I managed my best fuel economy so far.

2. Puzzlement

If you read all the way through that last paragraph, you'd have noticed the bit about higher than usual fuel economy. At the beginning of the day, I topped off my tank with 2.3 gallons, covering the 24 miles I had driven the past few days. You do the math. I was cringing at the thought of hard driving all day long. Yet at the end of the day, here I am, 214.5mi on the trip (really a few miles more; I didn't reset the meter until some 3 miles after filling), and the fuel light just barely on. You do the math, guesstimating 13gal used. WTF? Today was a barrage of stop and go traffic, fast crusing with frequent stops, uphill fast driving, downhill fast driving, a SMALL bit of fast freeway, more uphill fast, more downhill fast, and then stop and go traffic for an hour. How do I manage to get 16.X mpg having a blast, yet only get 15ish while driving around?

3. Probe

If you read through that second paragraph, I give you props for being patient - the probing is about to commence. I ask you, dear readers, to let me know how I "should" be driving to attain decent city and highway mpg.. There have been plenty of mileage threads, but they're **** to search through, because they nearly always devolve into a tirade of "OMFG YOU BASTARD WHY THE HELL DID YOU START ANOTHER MPG THREAD?!?!?! BURN IN HELL, SUCCUBUS!!!!" Anyway, I generally drive pretty mildly, shifting at 4k, crusing at 3k, and end up averaging around 15mpg after throwing in a bit of freeway. Should I be shifting and cruising higher? The last bit of this tank has been spent shifting at 5k, and cruising at 4. If this is ideal, that would be nice, as the engine is then in a more usable powerband. Also, on the freeway - I get paranoid because over a distance of 30mi or more I can see my needle drop a few clicks. How the hell should I be cruising to use less gas??




The sum of this entirely-too-long post is: I love my car; I do not understand how little gas I burned today; how can I keep up that relative miserliness?




P.S. for those still awake, those 24miles were spent crusing around city, with a few redlines. No uphill, no freeway, nothing too wacky. No idea how I managed 10mpg, but I'd desperately like to avoid repeating that.

Jasonawojo

iTrader: (2)

I've found that unless I intentionally REALLY baby the car, I get better mileage driving "spiritedly" than normally. This car really loves being run through it's gears. Even autocrossing generally doesn't effect my overall mileage for that tank--which I find amazing.

As for your average mileage--different RX8s seems to vary significantly in what their average mileage is. More-so than any other car I've read up on anyways. Your numbers (15-16) are roughly what I saw on average before tuning my car, and I generally try to cruise around 3K even. That keeps it below ~3750 or so when the first of the various intake values open up causing the car to run richer.

NoOdLe BoY

iTrader: (1)

stay between 3k and 5k for best results.

Hidef1080

I'm not 100% sure I understand what you are getting at but I am glad you like your car. I like my 8 too.


I have found that my average gas mileage stays about the same no matter how I drive it. I average between 18 and 20 mpg mixed driving. So I'm not sure how you should drive it outside of just don't over think it and drive like you feel. It is what it is....


I agree that the 0 to 60 [my moms “SU - Camry-O Van – Accord - V” is faster so the RX-8 is shight] kids have no clue.


I need more sleep....

G3tR3DDY2GR3DDY

iTrader: (8)

ill explain to my best ability while im intoxicated and not even looking at the keyboard why you best fual economy is best attained during aggressive driving.

while you are pushing your car, kenetic energy is used to push your motor in a circular motion. imagine how a turbo works. it is most efficient after a few thousand rpm.

now combine this with your fuel trim and ecu settings. What fuel octane did you use? If you used the typical 92+ octane then your ecu is set.

try pulling your room fuse, doing the brake pedal reset (search DIY) , then filling up with 87 octane BP or shell , then see your results. The rotary engine is most efficient at 4350+ when the secondaries are open, or in cruisng gear around 73 mph which is right before the catylyst temperatures are compensated and increase drasticly , decreasing your fuel economy.

So rule is, use 87 , reset your ecu fuel trim, stay below 74 mph, and you will will constantly attain 20mpg plus on a fresh car.

04RX8man

I've also done quite a few test with fuel mileage....while driving normally in traffic etc etc. I shift at aboout 4k rpms or so and any interstate/freeway driving I set cruise at about 72MPH which is a little below the 2nd ports open.

All highway with a/c on about 22mpg
All highway without a/c about 24mpg
City/stop and go with spirited driving about 17 or 18 (usually with a/c or windows down)

All on 93 oct (Texaco and Shell I seem to get best mileage from) also 8oz premix per tank...