Brian,

thanks for a really excellent post. At last we seem to be getting to the bottom of this mystery.

However, as a non-North America resident I am interested in whether this has the same implications in the rest of the world. As I understand it, the Euro 4 regulations for the European cars only apply for the first 100,000 km (63,000 miles) and for Australia it is 80,000 km (50,000 miles).

Do you think this would allow Mazda to run with leaner fuel maps in these markets? Or are you saying that lean mixtures at high revs will kill the cats very quickly.

Chris

 

"quickly" means "sooner than 10 years of anticipated levels of use". it's not as if the cats will melt down instantly, but that longevity will be effected in an unacceptably large margin over a long period of time.

 

Does it have to be the same cat in the Euro stage 4 emisions at 100k?

Say I , being a nonce, put a huge screwdriver through the cat whilst changing/repairing something, and had to buy a new one. What then?

Pbviously the cat sucks power, but is it restricting flow a lot? Would a 3rd party sports cat (available for elise,focus etc here) be better and/or legal?

 

Now here I was imagining that you had a carefully rotor shaped pony tail that slotted onto your seat back... :D

I haven't seen blue in the flesh, does it have the mica finish of the red?

 

The blue i sjust metalic. But very nice in the metal.

 

winning blue is sweet
its got silver flakes
while the red has gold flakes

 

Mazda UK is claiming 177KW on the web page last time I looked.
That is about the same as the 238HP claimed here..

 

Nope, nother mistake by mazda I'm afraid.

The power was 241ps, or 177kw(238bhp) but it was lowered to 231ps. Mazda just 'forgot' to change the kW value.

 

CANZOOMER

Keep up the good work , maybe i will do a barter deal with your upgrades on the rx8 ,we have great variety of fish and reptiles here in australia , to add to your collection , let me know of any that you are interested in .

Are you going to sell your upgrades here in australia???

 

Canzoomer,
I am trying to understand how the fuel remapping works (without you disclosing anything that you figured out that gives you a market edge)...

Do you remap the A/F onlt at WOT (Open-Loop?). Do you leave the stock maps for less than WOT (Closed Loop?)
Or do you have different maps?

I am trying to understand how throttle position plays into the fuel controller, and how you map it. I assume in open loop, it is just a simple look-up based on RPM (and maybe air flow). But in partial throttle, the varialbe become much more complicated, correct?

Just trying to understand how your mods would affect partial throttle, as I rarely have it WOT, I still want improved performance at partial throttle.

Rick

 

Canzoomer -
This may be way off, but while reading this thread I got to wondering -
It seems the ECU is keeping things rich to keep the cats cool;
Is this dependent on some sensor input? Is there something like a CAT temp sensor?

If so I was thinking that a sensor fault or sloppy tolerances could be a source of the poor MPG performance that some (like me) are experiencing. Perhaps variations in sensor performance could account for the way the cars seem to cluster into "low MPG" and "high MPG" groups.

Just some food for thought...

Dave

 

It is dependant on and has sensors for:
Engine rpm
Throttle opening
Air flow as seen at the mass air sensor
Oxygen levels at the O2 sensors
Barometric pressure sensor

The ECU takes these readings and based on a "map" of levels to use depending on these conditions, how much fuel to tell the injectors to squirt.
It also tells the ignition modules to fire, and varies the timing (advance) of this.

Differences that you see are probably caused by:
1) Driving habits ( biggest factor)
2) Fuel used
3) Altitude
4) Temperature
5) Barometric pressure.

 

Don't tempt me!
I keep tropical fish..

I will sell the kits to anywhere people want them. We have accounts with Fedex and DHL.

 

It varies a bit, but we are mainly adjusting from rpm levels, not throttle opening.

One of the goals is improved fuel economy. As people do not usually drive around at WOT all the time we have to account for this.
Like I mentioned before it takes many hours to take readings at all the different conditions to build the new maps. We are getting close to being done. Probably by the end of next weekend we will be happy with it, and ready to build and ship.

Build time mainly involves the making of wiring harnesses.
As we are making a harness that just plugs on to the existing harness to the ECU and to the ECU itself, it is a bit of work.

The connector on the ECU has 122 pins, about half gold and half tin contacts ( gold for data lines)

There are 5 plugs to hold all the contacts. that mate to it on the harness.

Biggest problem is that the cable plugs are easy enough to do. Just crimped connector terminals, but the mating male connector on the ECU is designed to fit in a circuit board, and is one bg connector. So, we have to modify this added male connector to receive all the plugs.
Lots of terminal crimping and soldering/wiring work to make the harness.
Programming the fuel controller, and installing it in the case is not too much work.

Once we get the volume up on the assemblies we can get a printed circuit board with connectors made to accept the plugs and that will cut the work by about half.

 

canzoomer, we spoke a few weeks ago, and I assume you will still be supplying this mod in Feb-Mar of 2004?.......wish I didn't have to wait that long for my car, but oh well....

with this fuel control system, you mentioned about 20-25hp?...

 

We will suppl yit as long as people want it.

As for the power, we are now debating what we should target.
We can easily get 20HP and still have cool ouput and a catalytic converter environment.
Some people wnat that as they will keep everything else essentially stock.

We can also get quite a bit more, perhaps as much as 32-35 but with higher exhaust temperatures, and more risk of damaging the first cat. Some people would rather have that, and take off their cats and stock exhaust and go for more power.

Maybe I should do a poll thread?

 

A poll thread? I think you should start a website :D

How about loading the maps from a USB key on start up (if connected) ... you could sell maps and tuned upgrades/fixes over the internet that people could download (serialized versions to map a serial number stored in the firmware to protect your investment).

Imagine an owner being able to build their own virtual map, based on the sampling you've done, then generate a custom map they could download to a USB key and test in their car.

Don't get your USB keys mixed up people - don't think the 8 will run too well with a fuel map of Prince singing Purple Rain!

 

I've been intently reading along with this thread for a while. You've done some outstanding work so far, Canzoomer.

1. Would there be any way for you to package multiple maps in a single, switchable controller?

2. BTW, have you produced any preliminary dyno slips? If so, could you post one or two? Images would go a long way in solidifying your initial customer base.

 

Multiple maps: Yes. But it is more expensive. Later on we intend to use the Apexi SuperAFC2 for that.
See:
http://www.apexi.co.jp/products/electronics/super.html


Initially, however we are shooting for a low cost unit that holds one map. We will probably offer that in two versions: 20-25HP, gentle on the exhaust and 30+HP, for modified exhaust systems.

We will also offer an ignition control module to go with this tuning level, which will add another 10-12HP. This absolutely requires a complete exhaust system from the manifold back, as it makes a lot of heat, and would destroy stock cats and muffler. Furhter the exhaust, when mated with this combination, will open up flow, allowing perhaps another 5-10HP to be produced.
This will definitely be a "track kit" as there is no way in hell it would meet emmissions testing requirements.

While the FC unit can be re-tuned, this will require the unit to be sent back to us for reprogramming.

I will be putting a web page up soon, and will place dyno charts on this to illustrate results.

We will use charts from the Mustang dyno we are using, and are planning to also get som runs done on a Dynojet, as these are more common.

Please bear in mind that this is an after hours project, so we are going as fast as we can, and still have jobs, lives, families, and need to sleep once in a while as well..

My strongest motivation to complete this is the fact that my RX-8 is a daily driver, and i get reminded every day about the need.

Thanks!
:D

 

Many of us have waited months just to get our RX-8. I think we can wait a few weeks to see the results of your efforts canzoomer.

 

Very nice job Carzoomer! I don't yet own an RX-8 but will most likely be purchasing one early/mid next year so this mod has me licking my lips.

Quick question about your statement above (and it may be a stupid and obvious question). Are you planning on using gold contacts with gold contacts and tin with tin to prevent corrosion from different metals making contact? The reason I ask is that even vehicle manufacturers make this mistake and have premature contact failure. The Nissan Xterra (which I own) and Frontier are notorious for having their fuel sending units fail prematurely because of this problem, rendering the truck useless. I'd imagine the same thing would happen with the RX-8 if the contacts leading to the ECU also start to corrode after 20-60K.

Keep up the good work!

 

Yes, that was the point I was trying to make ( badly apparently!)

About half the contacts on the ECU board connector are gold, and half are tin. One needs to make sure one has matched these parts with similar metals on the plug contacts that mate with them..

However, in a situation like you descrive with your Nissan, there are compounds that one can apply to the terminals that make hep them make a better contact and seal them from moisture and dirt.

 

Can zoomer

After all your hard work you will definetely need a holiday from your work , so come to australia , and chill out , you could bring your upgrades with you and supplement the cost of your holidays by selling them here in australia , you are very welcome we have great beer , weather , women , and one of the best deepsea diving spots in the world .
michael

 

Ah! I knew I was missing something!

I was in Singapore and Malaysia in July, and kept feeling this beer front blowing in from the south..

 

Canzoomer

In your quest to dissect the intricaties of the rx8 can you tell us how to increase the volume on the red line limiter as most of us can barely hear that beloved BEEPER as we try to find the rx8 nirvana .
Was told by mazda australia that the loudness of the BEEPER can not be adjusted , is that correct ??

Bye the way after a few good aussie beers i cannot feel the souhtherly winds only the call of the lovely sirens awaiting my sometimes uninvited advances which have had i must say a far better chance of success since my rx8 arrived , the girls all want to go for a spin , my scoring rate has vastly improved , as i am hoping will the performance of my car.

Allthe best .

michael