Hi experts in electronics

I am new here and so far I do not own a sports car powered by a Wankel engine.
But when recalling the rides I had in my father `s NSU Ro 80 I sometimes dream of having a modern Wankel in my 700 kg- Lotus Elise.

This engine should deliver at least 300 HP instead of the scarce 230 HP the actual Renesis is able to make and it should not weight more- better less - than this actually does.

Mazda `s new Wankel for fulfilling these wishes certainly will need a booster and this will require some remapping or in case it cannot be decoded for doing so another ECU will be needed. (Perhaps a Motec?)

But there are still some other companies busy in developing modern Wankel engines.E.g in Germany we have the guys from http://www.wankel-rotary.com[/url] and there are some rumours that Daimler Chrysler is busy in developing even an Diesel –Wankel - engine, too. Using common rail technology together with piezoelectric injectors
(See: http://www.sae.org/automag/techbriefs/05-2003 )
plus a good turbocharger made in Japan or by Borg Warner here in Germany, the chances to achieve an engine which consumes less than 290 g of fuel per kWh @ full power are not that unrealistic; and for sure the weight of such 300 HP engine can and should be less than the 275 lbs the Renesis still has.

( Remember that in Europe fuel prices are ca. 1,2 Euro per litre now ! --And that war in Iraq did not help to reduce it. Also in your country it ´s increasing more and more---)

Questions :

Who makes the actual ECU for the Renesis and which input goes into it?
Is there an air mass sensor like I have in my Miata ? ( Bosch / Denso system )
And the other main point: How does the knock sensoring , anti pinking system work?
Somebody told me that already in the latest RX 7 Mazda used the Ion Sensing Method

(See: http://www.vehicular.isy.liu.se/~lar...i_1998_CSM.pdf and

http://www.adrenalineresearch.com )

for controlling also their Wankel engine but I doubt this, tough I discovered that also Bosch, not only Saab, has been active in this field.

I hope to find some response in this forum because I saw that there are some posters writing more knowledgably and in better English than me.

Cheers Hartmut

 

As far as I know by info gathered here and there, the RX8 PCM (=ECU) is made by Denso Japan and run a software that looks similar to what Ford runs in their Black Oak ECU (Wankel specifics apart).

There is a MAFS indeed. The info about the PCM pin-out is actually available on this forum. It will give you an idea of all the inputs and outputs of the ECU.

The knock system is based on an accelerometer installed on the rotor housing. The in-chamber knock create a structure-born noise that is transmitted to it.
With the help of different filters, the knock noise frequencies are segregated from the other noise frequencies of the normal engine operation. Calculations including integration is made to define a knock level. Depending on this level, the PCM will decide to reduce spark advance or not. It's calibrated in such a way it will retard a lot to protect engine hardware and re-instate spark advance slowly in order to find an equilibrium at borderline detonation level (some light knock but without damage to hardware).

I'm aware of the Ion sensing technique, but as far as I know, it is not yet implemented on any production engine. To be confirmed however...

Hope it helps,

IKN

 

Yes this helps already for the beginning.
I know that the Miata ECU is also from Denso licensed by Bosch and this can be remapped by some experts who were able to decode the software for doing so.
I` ll have to ask my Miata friends.

Thank you again

Hartmut

PS
These accelerometers installed on the motor blocs or the rotor housings are special microphones only. I thought that in the meantime we can find some more elegant by which the engine can be controlled / monitored much better. Saab was a very innovative company before they were bought by GM.
Perhaps some Swedish RX 8 owners reading this can give more details.

 

The main processor is the Renesas 64F7055F40
see http://www.renesas.com
also https://www.rx8club.com/showthread.p...hlight=Hitachi