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The rotary is dead

Yeah, well.. Thats the way I felt when 500CC two strokes went away in GP motorcycle racing. :(
 
That is a bit sad after all the money and engineering Mazda put in over the years but there are thousands of engines floating around and will be for many years if you wanted to build one up for a car or aircraft.

The RX8/ Renesis did not do well for Mazda- tons of warranty issues and it was hard pressed to match the fuel efficiency, emissions and power of modern piston engines.
 
I'd bet it's not that big a deal. They also stopped production on the RX-7 prior to startup on the RX-8/Renesis. They've already got a new version of the engine (with significant changes, including a displacement increase & modified direct injection) at the prototype stage.

Charlie
 
My first run RX8 is still going strong....love it. :) I do hope the revisit it....decided not to build a plane with one though. But in the car it's been pretty bullet proof. Just did my big 60K mx....

Oh, and from the article:

the rotary design is notorious for its low fuel economy and high oil consumption
Click to expand...

It's designed to burn oil. That's like saying "wheels are notorious for rolling".

Anywho. :p
 
DCat22 said:
Oh, and from the article:

"the rotary design is notorious for its low fuel economy and high oil consumption"
​
It's designed to burn oil. That's like saying "wheels are notorious for rolling".
Click to expand...

Um, no... :eek:

Wheels are designed for the purpose of rolling. Engines are designed for the purpose of converting chemical energy into mechanical energy.

Rotary engines having high oil consumption is an undesirable consequence of a design compromise. They're designed in such a way that will burn oil, but they're not designed for the purpose of burning oil. There is a difference.

So that quote would be more analogous to saying something like "Brand A tires are notorious for high tread wear".

Anywho. :p
 
The Mazda Wankel rotary engine uses an engine driven pump to meter oil directly into the intake system, for the purpose of lubricating the combustion chamber seals.
 
Actually, the correct quote would be: "V-8 engines are notorious for burning gasoline"

:eek:
roee said:
Um, no... :eek:

Wheels are designed for the purpose of rolling. Engines are designed for the purpose of converting chemical energy into mechanical energy.

Rotary engines having high oil consumption is an undesirable consequence of a design compromise. They're designed in such a way that will burn oil, but they're not designed for the purpose of burning oil. There is a difference.

So that quote would be more analogous to saying something like "Brand A tires are notorious for high tread wear".

Anywho. :p
Click to expand...
 
Mike S said:
The Mazda Wankel rotary engine uses an engine driven pump to meter oil directly into the intake system, for the purpose of lubricating the combustion chamber seals.
Click to expand...

Yes, understood. It's a deliberate design feature that serves a purpose inside that engine. But it's not the purpose of the engine. :)

From a user standpoint, high oil consumption, even if by design, is a negative. An undesirable characteristic. And it is fair to point it out as such when comparing the trade-offs between different types of engines.
 
comfortcat said:
Actually, the correct quote would be: "V-8 engines are notorious for burning gasoline"

:eek:
Click to expand...

Again, not quite. More like "Engine A is notorious for burning more gasoline than engine B to produce the same power".

:)
 
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Burning oil Huh?

So the RX3 used quite a bit of oil. Then when the RX7 came out, Mazda reduced the oil consumption by, like, an order of magnitude. Then when the Genisis came out, it went down again, this time in order to pass smog. I curious from the RX8 owners out there, how much oil does a Genisis burn? I sure much less than an RX7 and much less than a Lycoming. JMO
 
From a user standpoint, high oil consumption, even if by design, is a negative. An undesirable characteristic. And it is fair to point it out as such when comparing the trade-offs between different types of engines.
Click to expand...

So, are you criticizing the Lycoming or the Rotary with this comment? The typical two rotor uses about a quart every 1500 miles of street driving. This equates to about 30 hours per quart. Most Lycomings would be jealous. :D
 
Ted Johns said:
So, are you criticizing the Lycoming or the Rotary with this comment? The typical two rotor uses about a quart every 1500 miles of street driving. This equates to about 30 hours per quart. Most Lycomings would be jealous. :D
Click to expand...

The original comments about high oil consumption of the Mazda rotaries were in comparison to modern automotive piston engines, not Lycomings.

It is also true that the Lycoming we fly also have high oil consumption relative to modern automotive piston engines. And it's fair to point that out as an undesirable characteristic of the Lycomings as well.

Anyway, I wouldn't describe any of this as "criticizing". These are just factual technical trade-offs between different engine designs. Oil consumption isn't the only parameter that matters, but it does weigh in to the trade-off analysis. Mazda rotaries may have many wonderful qualities, and some other qualities that are less wonderful. That their oil consumption is higher than comparable modern piston engines, is a matter of fact.
 
I will shed a little tear for the venerable Mazda rotary. I had an RX-3 in the late 70's, which totally kicked the butts of all the Corolla's, etc of the day, then a normally aspirated 86 RX-7 and a tweaked 88 Turbo in recent years. Loved 'em all, despite their thirst for fuel and lack of low-end torque (the turbo, mind you, kicked HARD and spooled fairly low in the rpm band). They were quick, smooth, and revved so beautifully. God help you and your eardrums if you ever had to hear one un-muffled, but the rotary is a unique and endearing piece of automotive engineering that I will truly miss.
 
Yes, yes, yes. :)

My only annoyance was with the article about using the word "notorious" for oil consumption, just because its different -- when it's completely expected and by design. (Mazda could have had you add oil to the gas, or used a separate oil tank too...but they went with the most consumer friendly/normal option. But it's still bizarre to consumers I suppose, that they ever have to add oil to a car at all....)

As for the "notorious" and gas mileage though... Yeah, I'm not going to touch that one. Don't get an RX8 for fuel economy. :p

johnny stick said:
I curious from the RX8 owners out there, how much oil does a Genisis burn?
Click to expand...

I add oil once every month or two... it's not an every fill-up kind of thing. I probably check it and top it off as often as I have with some older "interesting" cars I've owned before.

If you let it get too low you'll get an oil light flicker before anything too terrible happens (in my experience at least... :p :eek: :cool:). I keep a quart in the trunk.

I've been pretty mean to mine. It's treated me well (and it's an early 2004). I know many others that have not been so lucky though...
 
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