From R&D (NOW FROM PR)
 

I talked with the Director of R&D at Mazda about dynoing the RX-8 on a chassis dyno. He said don't do it until well after 1000-2000 miles have been put on the car, and the engine brakes in. . . "Said" is even the wrong word, he "implored" me to brake it in first...

So, get out and brake those engines in, and then retest them at, say, 5000 miles.

-----

8/22/2003

Official HP Revision: See http://rotarynews.com/view.php?id=206

thanks for the info, how about the ecu does it make a chage over after x number of miles ?

Thank you!


Any specifics on why the break-in is so critical?

Re: From R&D
 

On the latest dyno reported on the forums the car had 2215 miles on it but still came up with only ~180 rwhp.

Any info on the suspected XX,XXX miles ECU fuel mapping switch?

There may be a number of things that could account for the lower numbers.. These are some thoughts:

1. Did you hookup a wide band O2 sensor, and mionitor the A/F. It may be running rich to protect the engine durring break in

2. The tests have all been under warm/hot conditions. The "correction" might not be enough for a rotary.

3. The engines still may be tight and need to be broken in.


A little waiting and I should have more answers.

yes please stay in contact w/ Mazda to find out the real answer to the dyno question, and quell all these speculations/rumors

rumors are BAD mmmmmkay? :D

good stuff, thanks Dan. :)

Will do! Thanks!

Vince

This is definitely a step in the right direction.

Will await more detailed info from Mazda on this. Would really like to believe that their credibility is not at issue here...

Thank you rotarynews.com

Kind regards,
LK

Thank you, rotarynews!

I'm eagerly awaiting a definitive answer to this issue. Getting confirmation that this power loss is not a sign of a defective engine is pretty important to my decision whether or not to pursue getting the RX-8. I won't do anything until I find out the answer.

i just want to say you are really hardcore cuz instead of waiting for the dyno chart from Import Racer magazine, you guys take your own car out....

awesome

RotaryNews.Com.. working on info.
 

Guys:
Dan and I have been working on this since it first broke. We plan on getting the RN.com RX-8 on the dyno after a decent break in period. We want to give Mazda the benefit of the doubt here. Both of us drove PRODUCTION cars that actually felt faster and stronger then the PRE-PRODUCTION models, so we know the cars have the power.

In the background, I've been talking to folks and trying to get some valid information for you all. We know of a few other 8s that have been dynoed with similar results. Please look for an upcoming story on this at RotaryNews.Com very soon!!

Guys remember that Mazda can and probably will NOT comment on this publicly, until they have all of the facts and can present them in a way that will be satisfactory to the consumer and their own marketing and legal departments. I'm sure that any OFFICIAL Mazda comment, be it positive or negative on this issue, will be well thought out and forthcoming. Unfortunately, this is one of the issues we face living in such a litigious society. This of course is NOT to imply that anything is wrong with the RX-8.

The statements that were made to Dan by Kelvin, were directly in regards to the RN.com RX-8 being dynoed, but should be followed as a recommendation to all thinking about it. Nothing official should be read into Kelvin's statements to RN.com on this issue.

We'll get to the buttom of this and we thank all of the folks who to date have contributed their dyno sheets and commentary.

-Bern

thanks dan and bern for getting into this quickly. glad to have you guys on the job:)

re
 

Regarding Dyno, found this little interest read on page 64 of SCC, Sept '03 issue. They were trying to Dyno their test cars: EVO, Audi S4, M3, and 911 4S.

That is interesting! Anyone heard of such a dyno that will properly test these cars, (hopefully) including the rx8?

Question
 

Is there a loss in horsepower across the rpm range or only at peak (8,500 rpm)? If it is only at peak, sounds like ports still not opening.

Looking at the dyno plots, it certainly appears that the tertiary ports are opening just fine. I suppose it's possible that we're seeing the ECU cause the drop at port opening and that it's really not, but I doubt it. This appears different.

Dont believe everything you read, I have personally seen several E46 M3's dyno succesfully on a dynojet.

BTW, a broken in car might dyno 5-8hp more to the wheels than a car with 200-600 miles on the odo. but not a lot more. Ussually they dyno within 3hp.

Re: RotaryNews.Com.. working on info.
 

Bern, thanks for the update.

Yes they can comment very quickly if they know what is going on. It doesn't take a team of lawyers to tell the RX-8 customers, "When the car hits 4K miles the aggressive fuel maps kick in and the car will then be at full power."

IMO, they only need precisely written legalese when they have a problem or don't know what's going on.

-Mr. Wigggles

Re: Question
 

On the Dyno plots, the power is reasonable up to 6000 rpm. It is from there on that the power isn't with-in the power specified by Mazda from their web-site or the torque (and thus power) curve from their press-kit.

-Mr. Wigggles

That makes sense but all of us who've participated in the pre-order program no how incredibly bad communication from Mazda is. I have little doubt that the engineeers know what's going on it's just that either the lawyers or the marketeers or the public relations guys are once again off the mark on this.

I've made the same point several times as well:

If things are working as designed then we should be hearing from Mazda this week or next. All they have to say is "we currently believe the vehicle and engine are working as designed, more details will follow in a few weeks'. They don't have to say anything about possible ECU remapping (automatically or via dealership) or that the car might have 30% transmission losses instead of 17% etc. They don't have to tell the public (us) this either, just notify the dealers that if anyone asks about HP issues then this is the message to give them for now. My dealer has heard nothing about this yet.

The longer it takes Mazda to make any kind of announcement the more likely it is that there is a real problem and they are scrambling to research it and getting lawyers involved for wording.

btw....has anyone else noticed that they took the "Specifications" tab off the main USA RX-8 page (http://www.mazdausa.com/MusaWeb/rx8/rx8_main_flash.jsp) Are they trying to avoid something?

Hmmm, odd but they still quote the expected power on the 'build' page:

247 hp 1.3-liter RENESIS 2-rotor, 6-intake-port, rotary engine

You need to go through the Build and Buy and then download the specs as a PDF file. Why they did it that way? WHo knows.