Actual Rotary Displacement Request

[Libor]

Originally Posted by RICE RACING

there are no aftermarket ECU's set up to run the true Wankel cycle or count the individual rotor faces based of its ACTUAL cycle

Peter, I was curious about something. Would there be any benefit in engine control with ECU of such abilities? Like better fueling of individual chambers?

[RICE RACING]

Originally Posted by Libor

Peter, I was curious about something. Would there be any benefit in engine control with ECU of such abilities? Like better fueling of individual chambers?

There are some of us who are using this kind of bespoke *aftermarket* true rotary ECU and have been doing so for a long time!

Yes there are major benefits!
Mazda racing ECU's and stock ECU's are of this type 1080 deg true Wankel cycle, it is the only way to truely look at the engine.

Otherwise you do need to do alot of conversions to adapt all the other ECU's, not to hard to do, but most dont get it, especially when you are looking at things like control of injector opening and closing degree's etc.

[scotty305]

Interesting question, Barry.

Originally Posted by RICE RACING

There are some of us who are using this kind of bespoke *aftermarket* true rotary ECU and have been doing so for a long time!

Yes there are major benefits!
Mazda racing ECUs and stock ECUs are of this type 1080 deg true Wankel cycle, it is the only way to truly look at the engine.

Otherwise you do need to do a lot of conversions to adapt all the other ECUs, not to hard to do, but most don't get it, especially when you are looking at things like control of injector opening and closing degree's etc.

Mazda stock ECUs are only capable of measuring 360 degrees of eccentric shaft rotation; since the trigger wheel is mounted on the eccentric shaft it cannot discern the difference between one rotor face vs the other three. As far as the ECU is concerned, the rotary may as well be a two-cylinder two-stroke that displaces 1.3L per 360 degrees.


In a similar fashion, you could compare a 1.3L two stroke piston engine to a 2.6L four-stroke piston engine... both ingest the same amount of air in 720 degrees, but the 1.3L two-stroke occupies less space and will weigh less assuming similar materials are used to build both engines. Is this starting to sound familiar? If I'm not mistaken, the two-stroke should have less torque at low RPM greater fuel consumption than the four-stroke. I'm not an engine expert (rotary or piston) so please correct this if I'm wrong.

[RICE RACING]

Originally Posted by scotty305

Interesting question, Barry.



Mazda stock ECUs are only capable of measuring 360 degrees of eccentric shaft rotation; since the trigger wheel is mounted on the eccentric shaft it cannot discern the difference between one rotor face vs the other three. As far as the ECU is concerned, the rotary may as well be a two-cylinder two-stroke that displaces 1.3L per 360 degrees.


I'm not an engine expert (rotary or piston) so please correct this if I'm wrong.

No mate they use 1080 in programming and can measure it with a 360 wheel on the crank



You may not know where each individual rotor face is but that is not an issue so far as knowing the actuall Wankel Cycle and when to trigger things.

[j9fd3s]

Originally Posted by RICE RACING

No mate they use 1080 in programming and can measure it with a 360 wheel on the crank



You may not know where each individual rotor face is but that is not an issue so far as knowing the actuall Wankel Cycle and when to trigger things.

ah yes, good point! one of the rotary ADVANTAGES is that each stroke is 270 degrees instead of 180 like a piston engine.

you are wrong though, piston engines suck all the time

mike

[RICE RACING]

Just remember

Each engine is only *honestly* rated for displacement AFTER (ALL OF ITS ELEMENTS) have completed one cycle of work.

Elements = ALL individual combustion faces
Cycle = defined by power pulse (or simply spark firing) *remember suck sqeeze bang blow*

It's not a hard concept to fathom honestly ......... some always struggle cause they don't know how the 2 storke or 4 stroke or Wankel actually work though!

Define the cycle!
Count the faces!
There is your answer for displacement!

Equivalence (like I mentioned in my second post) can be used to compare the 13B to other non wankel cycles (as defined by time to displacement), IE displaces 1308cc in 360deg or 2616cc in 720deg, but it only does its wankel cycle in 1080deg which my friends = 3924cc in 13B form, nothing less!