Mazda rx8 wankel efficiency nearly there? 7

[harveygp]

Looking at the fuel consumption of the rx8 in relation to the power output, it seems to be comparable with piston engine sport cars of similar (high) performance.

Doesn't that suggest that say a single rotor version of half the output (say 110hp) but in average use having a wider open throttle and only half the frictional loss would give a very acceptable power unit for a small saloon with good economy too.

The improvement over the previous rx7 engine seems very impressive but has been got through careful attention to detailed understanding. So the basic engine topology has much more to offer that anyone would have guessed a few years ago.

Should the industry in general be taking a new look at the Wankel topology? Maybe it already is?

Any comment from those who know a bit more than me/

 

[r4360]

hi,I heard a 18b two rotor engine, a three rotor 21b, both in drag cars, and the four rotor mazda lemans engine, and can't help but to hear a four cylinder engine exhaust note in the two rotor engine, a six cylinder, or a two stroke triple engine exhaust note,in the three rotor engine, and a 180 degree header,cross plane crank engine exhaust note coming from the 4 rotor engine, can that be explaned? or am i imagining things. thanks Pat

 

[headintheclouds]

HarveyGP,

You are correct. Some posts have been dumped. Mine was one. There was no emotion in it. Just a thought I had regarding comparing recips and rotaries. I guess it didn't sound engineery enough. I'll have to go back to school and take the "sound engineery" communications course.

 

[NormPeterson]

. . . and can't help but to hear a four cylinder engine exhaust note in the two rotor engine, a six cylinder, or a two stroke triple engine exhaust note,in the three rotor engine, and a 180 degree header,cross plane crank engine exhaust note coming from the 4 rotor engine, can that be explaned?

At least partly by the general exhaust configuration. Did all of those engines feature single exhaust systems or at least was there a portion in each through which the exhaust from all rotors passed (similar to the "X-pipe" arrangement that's commercially available for certain US V8 engines)?

Norm

 

[r4360]

the four rotor mazda lemans engine dumped its exhaust into a four into one exhaust, the other engines, the two rotor and the three rotor engine where turbocharged.It was expained to me that the two rotor engine had two eccentrics on its shaft with a 180 degree offset, the three rotor had three eccentrics on its shaft with a 120 degree offsets, and the four rotor engine had four eccentrics on its shaft with a 90 degree offset, and that explains the engines similar exhaust note to the 4, 6, and eight cylinder engines.