Michael,

Agreed, I've averaged 14.6 MPG over 7,500 miles on 85% city driving. I haven't seen any gain over time and the EPA numbers stated for the US market seem off. I heard a lot of discussion about MPG improving over time, I personally haven't experienced it. 15,000 miles seems like a long time for it to start kicking over. I recall much earlier discussions when we didn't now mazda reflashed the PCM/ECU because of catalytic regulations and everybody was saying, oh it will "kick-over" at 2,000, then 4,000 then 6,000, etc, etc.. Just sounds like the same old story to me.

 

I have heard no real source of that, so reference would be good!

The RX-7 3rd Gen models DID have a 20,000 mile switch, but that is the only one we have seen so far.

Where did you see this for the RX-8 ??

 

I heard same thing from a tech at mazda.Slight mix change at 15k

 

i still don't understand why mazda would make an ECU that would give us LESS power and LESS gas mileage until 15,000km unless they could give us that straight from 0 km on the odometer. unless there is an underlying reason (something about the rensis perhaps?) i still won't believe that the ECU is going to change at 15,000km and start giving me more power and better gas mileage.

not to dismiss this information as false just yet, but that sounds like exactly what i would say if alot of my customers were complaining about performance and fuel economy. my 2 pennies.

 

You said you used only the usual amount of gas, but, Stealth, if you were driving hard and used the usual amount of gasoline, that would mean thet the gas mileage was better?
felix

 

Until we get a few tankfuls under our belts it will be very hard to say for sure.
We set this map up to be cheap on gas up to 5,000rpm, and then make power above that.
I can say that it should not use more fuel, but I am not sure what savings there will be until we get enough data over time.

 

The 2nd gen RX-7's also had a 20000 mile switch. Actually it was a seperate wheel in the odometer since it was not digital back then. This wheel was hidden out of sight behind the cluster but you can see it if you take the instrument cluster out. It was only in that car so that if anyone rolled back the odometer below 20000 miles, the 20000 mile switch would be able to stay at this number. Back then it only kept a record of any tampering that rolled back the odometer this far. It didn't do anything tho the cars tuning whatsoever. I'm not sure if this was the case on the 3rd gen RX-7. That car always had full power even from the factory. Mazda used to have dedicated rooms full of engines on engine dynos getting broken in properly before they were installed in the cars. They did this because they knew that people would just rag on them from the very start. That was a smart move on their part. I have not seen any info about Mazda breaking in the Renesis before it gets installed in the cars. It would make sense for them to back off the power or add a lower rev limiter for a certain number of miles but 15000 miles seems overly excessive and I am very inclined to cry bs on this information. The guy may be reputable but if the person that told it to him is wrong then obviously he will be too. I'll believe it when I see it.

 

Canzoomer: You mention that the map is set ot be miser under 5K. Has the power curve under 5K been affected? Has the power low down been sacrificed for economy? The last I had heard about this you where just doing an overall optimized map. I really dont want to lose power under 5K since this is where I am most of the time in traffic.

 

No, not really. Mazda had made that area pretty lean to start with, and we kept with that theme.
What we did mainly affects the range after the secondary intake runner section opens. We give it a couple of hundred rpm for the airflow to stabilise, then we hit the tune fairly hard.

It takes this smooth stabilized air flow and adds the gain fairly suddenly, ramping on to full power in about 200rpm.

this gives a "turbo like" rush at 5,000, and steady power climbing to 8500.

We wanted to see highway speeds staying economical, and high rpm range full power levels.
It turned out to be possible to bring that power range down lower than stock high ouput rpm zone.

That means, for example, when on the highway at 65mph in 6th gear, you can drop one gear into 5th to get into full power range, instead of having to drop to 4th, as in a stock RX-8.

Making that 6 to 4 shift is never comfortable, and screaming the revs so high is also harsh.

Another example is 3rd gear at 35mph, where the same range comes into play.

One can still do regular driving at normal economical style, while having the usable power immediately at hand.

 

i'm just a little curious, canzoomer...

when you say "we give it a couple of hundred rpm for the airflow to stabilise"... does this produce a noticeable discontinuity. like if that power were there assuming that airflow was already stable for that few hundred rpm, would that difference be significant at all?

 

Why can't we get some before and after G-tech graphs?

G-tech doesn't calculate HP correct but it can output acceleration in g's. I would like to see the difference between stock and modified.

10% more g's equals 10% more torque equals 10% more HP at any particular RPM.

-Mr. Wigggles

 

zoomer: Cool. Thanks. Thats what I figureed but I wanted to re-assure myself.

And yeah, I think most people are just dying to see some sort of plot/video/wav of the car with the unit installed. I hope them web pages are coming up soon!

I am especialy antsy now cause my fiance is giving me the Borla for x-mas :D

 

That explains a lot....

'Zoomers point about the shift points explains why I have been in 3rd and 4th so much, the power band has definitely widened. Stock, you never get over 7500 because it gets weak - there is no point going higher, and you need to shift up to keep accelerating.

Gears 3 & 4 are now SO useful, and the whole region from 5k to 9k is in play! I may never use 5th or 6th again!

I can't WAIT to see some plots, the curve must look radically different.

Sorry for not being more active with replies, I've been out driving......

S

 

i need 5 bills stat.

 

Well, I could send you my electric, gas, water, cable, and trash bills... :D

 

Ohhh!

That's funny.

Vince

 

but first i'd have to pay my phone bill, car payment, credit card payment first

how i wish i could dump an endless supply of money into my 8.........ina perfect world maybe.

 

I just wanna say first that Stealth...you're a vicious, rotten bastard; I was just fine with my 8, now I want this mod you fiend! :D

I also noticed that many posts are making the error of transposing 15,000km to 15,000 MILES for the ECU change Mazda tech is talking about. The conversion to miles from 15,000km is actually 9,321 miles so many of us early buyers should be nearing that point real soon (some are already there probably). I have 7,600 miles on mine so sometime near the end of January with my normal driving routine, I should hit the magic mile number. I'll report any noticable change.

I recall reading another thread somewhere that this mod cuts the life of the catalytic converter in half? Does this mean worse emissions or just a shorter cat life?

 

WHAT'S GOING ON??? . THIS ECU MOD COULD BE A MAJOR MILESTONE IN OBTAINING MORE POWER AND THE PEOPLE WHO HAVE THEM AREN'T REPORTING ANYTHING!!!. CAN ANYONE GET AT LEAST A G-TECH AND REPORT HOW MUCH JUICE CANZOOMER'S ECU IS PUMPING.
THANKS

 

We don't *KNOW* what the actual life will be.

We DO know that the original tune, for example as sold in Japan, would have met the current 2003 emissions standards, whic requires a converter lifespan of 50,000 miles.

We also know that the car as sold is now supposed to be compliant with the new EPA2 spec for 2004 model cars, which requires a 120,000 mile cat lifespan.

What the life will be with our tuning mods is completely unknown, but it *SHOULD* be similar to the original, so I expect it will provide at least a 50K mile lifespan. Only long term use on a few cars will provide a definitive answer to this question.

 

I had planned to do that yesterday.

Then we had a freezing rain storm, so it is well on impossible to do a 1/4 mile run, let alone safely.

I hope over the next few days to be able to get this done.
We are sending some units to some people in a warmer climate this week. After that we will get some figures.

 

I'm sure I already know the answer to this, but what are the chances of this ECU output modifier working on an automatic RX-8? My guess is no, since there are fewer intake port actuators.

 

 

^^^^ Too Funny!

 

Redshift: The fact of the matter is that we want to know how Canzomer's ecu is performing. Dont write remarks that are out of place. Big deal if they were written in capital letters. This is a forum for RX-8 information,not a Grammar school. Get a life.