Thanks, rx8cited...

Maybe it would be fun for people to see what it's like in an RX-8 on the track. I film my driving using a webcam, with the laptop buckled tightly into the right seat.

- Lap 1 - 15Mb
- Lap 2 - 15Mb
- All laps - 64Mb !!!

There's no sound - the files would have been more huge, and with the windows open it was not much more than wind noise, anyhow. Lap1 and Lap2 are in All laps. In the last lap of "All laps", the engine cut out briefly on the long, high-speed stretch. That's when I saw my yellow low-fuel light on, and was pretty sure I only experienced fuel starvation. But this blinking engine-shaped idiot light came on, so I backed off the rest of the last lap before taking it into the pit. It all came out OK - the engine light went off when it decided it was nothing major, and I filled up my 8.04 mpg tank.

The curve that needs the power is the first right after exiting the pits, which is also the first right after the start/finish line. It starts a bit tight, goes uphill, then gets REALLY tight. That's when the RX-8 does best with full power and a little slide.

The car really held its own against some fast cars. However, you'll see a Z06 gobble up the RX-8 on the straightaway... 400HP vs. 238HP is no contest. An unidentified BMW also pulled away pretty strongly. What I need is a third rotor!

 

Nice Post RandyP,

+++Karma Points

RacingBeat has a 3 rotor engine for sale. It runs methanol and get 1000 HP, but it costs $50,000. I was at RacingBeat getting my Cat Back exaust. They also said they are getting closer to finishing their bench for the reprograming the stock ECU, they said they had to fly a guy out here from Japan to figure out the coding. Once that was done, they tweaked it abit and are getting 10-15 hp increase, just need to finalize everything and in will be ready. The plan is you bring your stock ECU RacingBeat Flashes it then tests it on the Bench Engine and you get it back the next day. How does that sound RandyP???????
Also they are developing a closed box intake system that will be quieter then K&n's intake, but it is like 2 hp less then K&N's. It also looks like the stock intake, so no worries of Warranty Violations with just eye balling it. :D

 

DUDE!!!!!!!!!!
RUDENAEUR, you are amazing!!!! i was always worried about the mileage of the car and how it boasts a 24 mpg and i get about 17 especially with the high priices of gasoline here in LA. thank you so much for the tip and i never even knew about the TCS disengage . THANK YOU again

 

Uh... I'd probably go for the Z06. :o

I hope you like it... it's the system I have in mind. There's a thread about it -here- where you can tell people what you think of it.

It sounds like competition in aftermarket ECUs, and that's a good thing. After looking around this forum for a while, I'm getting more and more impressed at how well Mazda tuned this little 1.3L powerplant and its components. Of all the mods made by all the owners, ECU mods bring the most HP. Here I'm leaning towards Canzoomer Stage 1. I like to tinker and optimize things for my driving style and environment. CZ1 gives me detailed control over the ECU map. I also want to update the Mazda ECU flashes myself. Finally, CZ1 can be totally removed whenever I want the car in totally stock condition.

I'll probably look at the tires and suspension after the ECU. I'm interested in getting around the track quickly, and I think I get more bang for the buck in sway bars and sticky tires than other engine mods.

 

I've been ignoring the MPG claims, but for some reason I wanted to look into them myself last night. There's a question about Mazda's 24mpg figure, and whether DSC/TCS affects mpg.

I decided on an mpg test I thought would be reasonable for Mazda to conduct to get its freeway rating: 65mph, cruise control, clear night, still air, temps 60-63. Test is approx. 100 mile loop in very flat terrain, half in each direction to make up for any air movement and hills. Same gas - Shell 89 octane, same station, same pump, less than 30 seconds from the freeway. I shifted by the book: 14, 22, 29, 36, 46 mph (very boring). These speeds work out to 3000 RPM in each gear.

- With DSC/TCS on, 104.7 mi, 4.41 gal = 23.74 mpg
- With DSC/TCS off, 86.5 mi, 3.63 gal = 23.82 mpg

The test with DSC/TCS off was second. I turned around at a different place because it was getting late, so it's a bit shorter. The temperature was 1.0-1.5 degrees cooler, which would raise the mpg slightly. And while I tried to fill the tank exactly the same, I'm sure it was off by some amount... so to me these numbers are "the same". DSC/TCS should be left on for all normal driving because of its safety factor, but if you're driving hard in a controlled environment, turning the systems off lets you use all the power the engine can deliver.

As far as Mazda's claim of 24 mpg goes, I got very nearly that value. If I ran the test at 100kph/62.5mph I bet it would hit 24 exactly. I think it's amazing the car can go from 8.0 mpg at the track to triple that value for casual 65 mph cruising... or 19.4 mpg at 90 mph, A/C on at 100 degrees.

I guess if you're getting 17 mpg, you're just having fun with your car. :D I certainly didn't buy an RX-8 to drive around shifting at 3000 RPM...

 

[QUOTE=RandyP] I like to tinker and optimize things for my driving style and environment. CZ1 gives me detailed control over the ECU map. I also want to update the Mazda ECU flashes myself. Finally, CZ1 can be totally removed whenever I want the car in totally stock condition.

How much is the CZ1? Is it like 600$ and can anyone(laymen) change the mapping or could I get some advice from you on how to make the proper adjustments. Is it user Friendly to the point that I wont blow an apex seal. This is my first time having a really computerized car to trick out. My 1979 rx7 sooo much easyer to work on. That CZ1 seems to be a good choice since it is hidden in the spot where the stock ecu goes. For warranty issues. If I go with the CZ1 at least I can swap back my stock ecu easaly for when mazda snoops around the car, during inspections/oilchanges.

 

That's the right unit. There is a data cable and programming software for the CZ. You'll need those if you want to tune it (or have to). It's very important to me that the unit be fully removable; I'm wondering what will happen if RacingBeat flashes an ECU - then a Mazda dealer checks its software rev and maybe a checksum and finds out you have a little surprise in the EEPROM.

I'm no expert with CZ1, to be sure. I've read enough to know a lot of people bought it and liked it, and a few people flamed it. The flamings come from people who don't want to tweak, but something like this *is* for tweaking. You'll need to read the dozen or more threads on the CZ's to get comfy, as I've been doing. When you feel you know what it is you're buying and know the principles of its use, you should be self-sufficient (or find answers in CZ threads in this forum, or from Canzoomer). I think every question you'll come up with has been answered here, somewhere.

Take note of intake systems as you look around, and the many concerns that have been posted. I feel the safe route is CZ1 + RB Cat-Back, and nothing more for the engine. Use your own judgement, but from what I've read... intakes give little gain and have potential problems, flywheels change the car's driving characteristics and make over-revving very easy, and underdrive pulleys have been noted to cause severe damage. Call it frustrating - or call it excellent, optimized factory design - your choice.

EDIT: I just read about the Group Buy from CZ, and it isn't going well. Caveat emptor! I'll wait for a couple months and see what's left after the dust settles.


As for this thread...

... it seems we have been victims of a practical joke... or wishing thinking.

Has anyone, anywhere hit 24 mpg average city/highway? I nursed my RX-8 last night with nothing but pure cruise-control highway driving and it just about got to 24. The claim of 24 avg city/highway should have triggered my BS-sensors a long time ago.

... and that was the last post of the thread's author. It was made last September.

So... this is my last post on this topic. I've tested the heck out of this proposal, and I've come away with respect for the DSC/TCS system and no indication at all that it affects mileage. Performance is affected, but that's to be expected when DSC is trying to PREVENT you from getting sideways. It has to react to first indicators of trouble situations quickly - it can't recover you from a spin you've already entered. So, it's reasonable that we note improved performance when we're driving hard, but it's unlikely the DSC/TCS systems are causing the ECU to produce too little HP under normal driving conditions.

Have fun with your 8. It's a "pay to play" world, and winding it up to 7K every shift costs a bit of money. So does riding the X at Magic Mountain. If you don't believe it can get 24mpg on the highway, do the test I did last night and see for yourself. If you think you can get 24mpg avg city/hwy like the author did... maybe you're smoking something other than your tires?

 

Rotary Nut (automatic transmission) posted a few weeks ago getting around 26 mpg on a road trip. I'll try and find the link. Here it is: Its about time... 26 mpg Woot!

rx8cited

 

I checked out the thread and chose this as a good quote... then saw who posted it.

I know what I did last night, and it was the bare minimum power necessary to take the two round trips. My A/C was off, my speed 65 on cruise control, windows closed - everything set up for best mileage. (Note, the car has 2700 miles on it and may not be running as well as it will)

So... I had no A/C, 65mph, 6th gear MT and got almost 24 mpg... RN has A/C, 75-80, AT and got 26?

Someone in the thread asked what he gets on the return trip. That's an important question. I've driven in winds that add or subtract 4-5 mpg, and without a round-trip it's possible he had tailing winds the whole way. I also used the same pump each test, as different pumps cut off at different points due to different vapor capturing features or different pressures/periods in the pressure pulses used to determine fullness of the tank.

I have to think that Mazda would advertise 26 or 27 mpg for the car if it obtained it reliably. I'd need to see a more controlled test to be convinced that the car can repeatedly deliver that kind of mileage. I wouldn't give up my 6-speed for it, though!

 

I had a thought. If Rotary Nut's car reliably gets 26 mpg at 10 over with the A/C on, he should be able to run the round-trip test as I outlined and get even better mileage than 26. Right?

I think he's proud his car *got* 26 mpg, and I'd be impressed if mine did under those circumstances, also. I don't think he's telling us the car gets 26 mpg on the highway routinely.

And - back to the topic of this thread - Rotary Nut didn't claim he saw it in mixed driving, or that it was a 50% increase in mpg.

 

Noting will happen with Racing Beats Ecu, the dealer will reflash it and erase all previous programming on it, and there will be no error.

You then would have to send you unit back to RB to have the programming put back on it.

 

they CAN NOT advertise any mileage other than what the car tests at during the EPA testing. period. whether in the real world it gets lesser average or can reach a higher maximum under strict conditions. they are just not allowed by law. also someone said a page or 2 ago that 18 to 24 means an average of 20. not entirely accurate. the 18 is an average number for city and the 24 is an average number for highway. rotary nut is not the only person on this board to get above 24. i have seen several one way trips that have been over 24 including numbers in the 25 -26 range plus elara managed a 27mpg on one trip. they run the 2 tests 2 different ways. so you really can't average those to numbers. look at the window sticker and below those avg numbers you will see the range for each figure. will most of us ever see those higher numbers in the real world? no because you hardly ever have ideal weather and road conditons.

as far as your round trip being "more accurate" maybe so. but that is not how the highway epa test is done so i dont see what that proves, positvely or negatively, really.

 

Very interesting, i'm actually going to get up right now and go outside and give it a try. I will let you know how the mileage is over the next week.

 

[QUOTE=PoLaK]You will get better mileage driving at either 63 or 83 (and 96 if you’re willing) in 6th gear, if you plot your air to fuel ratios you'll see that these are the leanest points in 6th gear. (M flash)

So, air/fuel ratio is the only factor in gas mileage? Afraid not; air resistance is a major factor at these speeds, and it goes up at speed/squared.

Mitch

 

[rabid troll]
woohoo with dsc off it has so much more power! i can peel out and do continuous donuts now! when dsc was on my 8 couldn't do any of that! woohoo!
[/rabid troll]

[insomnia] so far my best 13 gallons has gotten me 290 miles, 75% highway, 25% street, with dsc on. turning dsc off has never made a difference.

 

Course not but I found it interesting that doing 95-99 yielded me a better MPG coming back from my dyno day then doing 75-80 going to my dyno. And the AFRs concurred.

 

One thing that was the dyno didn't capture was AIR RESISTANCE. That is going to put more resistance you the car travel than anything else at that speed. There is a lot more resistance put on a car at 95-99 mph than at 75-85. I doubt there is more gas milage at 100 vs 85. That would be difficult to swallow.

 

I went through some articles from Mazda about the DCS and TCS, appearently the traction control system controls the torque, if the tires loses traction, the torque is lowered (short version). It says this in the manual that comes with the car as well. So, if the tires slip at all, the torque will drop, producing less power.

I tested it out and so far have noticed some improvement in fuel economy (not much but enough to make it worth while).

 

Which is more important, a little more gas milage or the life of you or your loved ones riding with you. That is the question we must all ask ourselves.

 

I have to say I'm rather perplexed by all your obsessions with mpg.

Why did you all by such a performance car if you are just concerned with mpg?

I own an Elise and I've got to say I'm not fussed at being so much below advertised mpg rates as I just love reving the nuts off her and enjoying that fantastic acceleration braking and conering power.

So peeps for goodness sake like that last chap implied... go out enjoy your cars and be a prper petrol head.At least you US guys don't have to pay close to 45p a litre like we do in the UK.

Have fun

Love

ASHUS BUY AN ELISE!!!!!!!

 

You paying 45p a litre, where?

 

Why the bloody hell are you so bothered by our "obessions" with mpg?

Just because we're concerned with understanding and improving our mpg does not imply that we're not enjoying our cars.

Not everyone in the world likes your favorite ice cream buddy, so do you think you can respect that, eh?

rx8cited

 

Yeah, I don't understand why I keep seeing the "well, you bought a sportscar..." cop-out.

The issue is that hp/lb/gal, we are way under everything else out there and the EPA rated us much higher than what nearly everyone is experiencing.
So, we are curious.
I don't think there are too many people here that are so concerned that they would give their RX-8 back if given that option.

 

I have over 12k on my 8 with A/T and I use 87oct most of the time though I feel a little more power with 91oct gas. New with the cruz at 65 and A/C on I got 23.5mpg. I was happy, but it got much better! Now with same conditions I have on 3 seperate tanks got 27.5mpg. It's hard to just set there in the slow lane. People think "He's got tickets" or " He's breaking it in" or is "He's going for what can this thing really get gas mileage wise?" Most of the time I get 18-23mpg. Tomorrow I have a long streach that I have to do 55-60mph on. I'm going to set the cruz and see if it can do any better. The thing is I will be at 2000 to 2500 rpms and the torque is low and mpg might not be any better. I will let you know tomorrow.....

 

45pence thats in the uk.

try reading the elise forum to see how we do things over in the UK.

http://www.british-cars.co.uk/cgi-bi...t&subject=2001

We seem to be more obsessed with improving performance and avoiding speeding fines than MPG but like someone said we all like different flavours of icecream.