AbusiveWombat

It's just lately that I've researched the rotary and have learned of all it's advantages over a conventional cylinder engine. So why don't we see rotary Miata's, 6's, and Protege's?

It's probably pretty expensive to hand build each rotary for the RX-8. So why not mass manufacture the rotary at different levels for each car, similar to Nissan and their 3.5L V6? I figure that this way Mazda could throw a bit more money into R&D to fix the major flaw with the rotary....torque....just kidding hehe...the fuel consumption.

With the current RENESIS alone you could already cover the whole spectrum of Mazda cars (Mazda 6 excluded because of the higher torque of the V6). Just offer detuned versions for the Miata and Protege.

If only the rotary had near the R&D that conventional cylinder engines have...

neofreak

iTrader: (1)

We're at the begining of a revival of sorts, and perhaps if the RX-8 does well, more cars will come with it.

Back in the 70s most of Mazda's cars were rotary, but due to numerous factors (oil crisis/bad reputation) they faded away.

Now that we know for sure the 8 is coming, I can definately say that for as long as I can, I will be rotary powered.

inittab

Rotaries make great airplane engines. High reving and reliable, who could ask for anything more in and airplane engine?

Toadman

They are also used in industrial compressor powerplants and fork-lifts, although converted to propane or natural gas. The rotary works well with many fuels, including hydrogen. Kinda' kills the reliability stigma, don't it? :D

ACRX8

I read an artile about a year ago where a boat offered a rotary engine. I think the boat was around 22 feet.:D

inittab

Hell yeah!

http://www.boatingnews.com/rotarymarine.htm

ACRX8

Thanks! :D

TreknMazda

Here's a list of vehicles with rotary engines. Note there is even a lawnmower!

I didn't see it on the list, but isn't there a TANK powered by rotary, too? :D And at one of our East Coast Rotary Expos, a person entered the car show with a wankel powered Lotus!

ZoomZoomH

iTrader: (1)

is that a supercharger sitting on top of that engine???

inittab

Yes! IT could be an Atkins Rotary setup

wakeech

yeah, the wankel could have very serious potential in widespread marine use: you get nearly the cleanliness of a 4 stroke piston, with the compactness, simplicity, and power to weight of the 2-stroke (more traditional) piston outboard...
in the industry, lately the 2-stroke guys have been trying to match up with the 4-stroke emissions, where you get neat innovations like the Johnson FICHT technology, but i really think that the wankel could trounce even something like that (seeing as how FICHT engines in their current spec are regarded as crap) without too much trouble.

Jeff20B

That supercharger on the marine engine looks more like an Eaton. Notice the air filter on the end opposite the pulley? Anyway, don't get me started on how many uses there are for the rotary. Especially now with the Renesis. Too many to type

wakeech

welllll... you COULD use the wankel interchangeably with any motor, but it certainly wouldn't always be the better solution, all things considered, in many cases, and a turbine or piston type engine would work far better.

Jeff20B

Right. I steam locomotive uses steam to push on a large piston connected to the wheels. The next logical step was to eliminate the boiler, but they kept the pistons. Anyway, you're right that with some powerplant requirements, a piston engine is best. But then again, some of those requirements have been around longer than the rotary itself. I guess I'm trying to see outside the box (engine bay) here. Remember, most things out there were designed with piston engines in mind. We've got to think of ways to use a rotary instead. If for no other reason than to be different. :D

cueball

I work at a marina and I can tell you everyone I know thinks FICHT and Johnson in general are crap. You want a good engine get a Yamaha. They are the best (at least in my opinion).

Sorry to get off topic. But like everyone else said, the uses of the rotary are limitless. The only thing the rotary wouldn't excel at would be towing (then again a big *** supercharger could fix that:D).

Jeff20B

I've heard stories of REPUs towing stuff and doing it really well (embarasing V8 powered trucks). I think Mazda ought to tweak the Renesis' ECU for more torque and throw it in a souped up B series pickup and call it REPU2 or whatever. Or what I'd like even better would be the rumored 10MM wider per rotor 1468-1472CC or 14C or 1.5L or whatever they decide to call it, larger displacement Renesis instead. That's drool-worthy.

wakeech

i think it's a fantastic concept (something i'd thought of, then went "oh, they already have that?"), but just engineered poorly. IF someone like Honda or Yamaha, or another 2-stroke wizard got their hands on that patent, you'd see the world of 2-strokes flip on it's head... think about what that could do properly implemented in MotoGP

wakeech

let's not get into the "what's better: wankel or V8", 'cause in different applications, either may win out. in the case of trucks, i'd really have to say that the 10mm stroke of Mazda's wankels loses out to the +100mm stroke of +400ci V8's... i don't care how you cut it, in this application, a long stroke, high displacement piston engine is gonna pull harder at low (engine) speed... given also that they're cheaper to make right now, it's hard seeing the REPU making a strong comeback: there's no real advantage the rotary has here...
...but applied in machines built only for speed, well, it's obvious, isn't it??

Schneegz

I know it's been done before, but I'd like to see a motorcycle with a rotary engine. Specifically, I'd like to see a sportbike with a 1000cc version of the Renesis.

Rotaries are smaller, lighter and more powerful than comparable piston engines, and they can achieve higher redlines. That combination makes them PERFECT for motorcycles. Also, the comparable lack of torque would not be an issue because sportbike engines are tuned for greater hp than torque anyway. Stick a rotary in a great sportbike chassis and I think you'd have an instant winner on your hands.

The Norton motorcycle company tried it back in the 80's. Unfortunately, they contributed to the rotay's bad reputation because Norton, like every other British motorcycle manufacturer of the time, didn't know the meaning of the term "quality control".

I wish Mazda would colaborate on such a project with one of the big Japanese bike manufacturers. The ideal would be a Mazda rotary in a Honda chasis. But a more likely combo would be a Mazda rotary in a Yamaha or Kawasaki chasis, since neither Yamaha or Kawasaki build cars, and are therefore not in direct competition with Mazda.

wakeech

yeah, i think a 300-500cc bi-rotor wankel would just absolutely rock... that would be so freakin' unbelievable... woah... :D

Farsyde

torque is almost a non-factor in motorcycles though (almost) since they are so friggin light

CypherNinja

Screw a sport bike chassis.... I'd put it in a Vespa.:D :D :D

Midnight Flyer

I remember reading somewhere a number of years ago that the rotors turn at a given rate, but that through gearing the output shaft spins at a double or more the rate of the rotors.

For an aircraft engine you actually need to reduce the speed of the shaft going to the prop otherwise the tips will be constantly braking the sound barrier and the plane will have trouble flying.

The added size and weight of the PSRU reduce the utility of the rotary engine in a plane. I wonder how hard it would be to make the output shaft rotate at the same speed as the rotors, or is that impossible due to the way the engine in built.

wakeech

the e-shaft makes one revolution per every 1/3 revolution of the rotor (which is once around for every power stroke)... rpm is a measurement of the output shaft speed, so in reality, the rotors are spinning slower than the e-shaft, and not the e-shaft is going triple the speed of the rotors, if you know what i mean....
in teh RENESIS, at redline, the rotors are only going around at 3k, while the output shaft is doing 9k.

RotaryXTypeSH

they dont use it on every model is because that if they make it for every single car that they make then it's not going to be special anymore, ROTARY r suppose to be special!!:D