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A possible look at the future - somewhat off topic

A couple or three decades ago, I thought by now most cars would be using Wankel type rotary engines, but seems like Mazda is the only one to carry the torch, and my hat's off to them.

Does anybody have any theories as to why a lighter, more powerful, less moving parts, rotational rather than reciprocating powerplant is not more popular ?

Well, here is a link below to a very surprising and enlightening article that discusses another alternative for you crazies

http://www.bankspower.com/Tech_dieselperf.cfm

Talk to owners of the last RX-7s that were blowing engines a lot. And the leaky seals on the rotor. And they are a little worse on MPG. If diesel technology ever becomes mainstream, I think then it wil be funtime. I'm still waiting for a TDI hybrid from a VW-Toyota joint venture.

two words: gas mileage

It’s my understanding that the issue with the Wankel is emissions, the combustion chamber has a lot of surface area which causes the trouble.

I’m a long time fan of diesel, been driving them since the ‘80s. Today’s direct injection (turbo) diesels make great power are very efficient and do quite will on emissions, I think VW is leading the way in production models. Though I believe their true promise is currently being overlooked (at least in the automotive world), they would excel at fixed/narrow RPM power generation for hybrids.

Now if you really want to learn about some exciting and nearly revolutionary technology, do some reading on Homogeneous Charge Compression Ignition (HCCI). Here’s a link to get ya started:

http://www.me.berkeley.edu/cal/HCCI/

and

http://www.tfd.chalmers.se/~ogink/

Gary

Mazda is talking of going HYBRID on the rotary wankel. Would be similar to what Honda and Toyota has now. The rotary gets really great gas mileage while cruising speed, but horrible at low RPM city low speed.
So the ideal match is for them to match up a Hybrid electric for initial starts and low RPM, but when out on the open, for the Rotary engine to then takeover. The Wankel engine produces the most power around 10,000 rpm, and that is the spot it also gets the best mileage.

The reason for the oil seals going out is that the engine was run before got up to temps the proper way, and again, having an electric assist would allow for the rotory to warm up properly before it gets pushed.

I know this is engine related.....but it's less subaru specific, so I'm going to move it.

Two words....Apex Seals! When they would start to go I would mix some gear lube with the oil and it and that worked better than most anti-leaks you could get at the store.

I miss my RX-7's. They no longer use wankel engines. They use Ranesis engines.

Wankel is another name for rotary. The Renesis engine is still a rotary/Wankel engine.

Oh, and RX8's are ugly, slow, gutless turds.

dont RX8's have a 3 rotor? perhaps it is just the heavy car and crappy tune of the motor.
rotaries are cool, Ive always admired how different and capable they are. once I find that perfect toyota starlet maybe I'll start looking into a rotary.
sorry for the semi-hijack...
diesel is definitely going to play a bigger part in the future. diesel has nearly 35% greater energy density than gasoline. it requires less refinement, which theoretically makes it possible to cost less than gasoline(a whole other can of worms).
There have been some exciting developments in biodiesel research, which, if turn out to work well could really take off. soy based biodiesel has about a 30% greater energy density than gasoline.
algea based biodiesel:
http://www.unh.edu/p2/biodiesel/article_alge.html

whats worse, is that we are RAPIDLY approaching whats known as peak oil. in other words oil production for a given supply can be described by a bell curve, and we are nearing the peak of that curve for world oil. best estimates are 2008-2011. after that, the supply will begin to decrease while worldwide demand keeps increasing. the economy is basically fucked. and btw this is not a hoax or conspiracy theory.
stuff like biodiesel and kinetic energy is hopefully what will save us.

206er wrote:......kinetic energy is hopefully what will save us.

explain...

wind power, ocean power. the ocean has a HUGE amount of kinetic energy available. buoy systems, floodgates for tides, etc.

yeah.....just wasn't sure what you meant by kinetic energy

Here is a good article about Mazda and their intro to rotary all the way up to the RX-8 of today.

The only 3-rotor street car was Mazda's Eunos Cosmo. It was a heavy sumbitch. Its performance was similar to an SVX.

And Greg, where's the article?

Legacy777 wrote:yeah.....just wasn't sure what you meant by kinetic energy

I thought maybe he meant coasting to the stop signs to save gas

Greg, what article?

I can't recall what it's called, but some Australian company is experimenting with a boxer-layout (the prototype was actually built using a Subaru engine as a base) that has the opposing pistons on one connecting rod, like the double-acting set up in that type of steam engine (still my personal favorite). I'd like to see rotary valves come in as a cheaper alternative to electro/hydraulically actuated poppet valves. Both provide excellent to near perfect valve timing/opening (lift) adjustment and reduce wear and power consumption.

If my Mazda 3 had come with a direct injection turbo diesel, I'd have bought that. Not a rotary though - I've always felt they're a great idea on paper that just doesn't work out so well in real life (like the Segway scooter).

I don't know why the Miller cycle isn't employed more often.

Steve

evolutionmovement wrote: I'd like to see rotary valves come in as a cheaper alternative to electro/hydraulically actuated poppet valves. Both provide excellent to near perfect valve timing/opening (lift) adjustment and reduce wear and power consumption.

rotary valves are way cool. I remember watching a video of some company that was doing some heavy duty research into rotary valves, and they had set up a small block ford with some rotary valve heads. it got like 30mpg in a mustang or something, and still made a bunch of power. there is some problemwith making rotary valves durable though.
also, I dont know why more companies arent experimenting with diesel/electric hybrids more. chrysler did back in 1997 or so, and with a full size dodge stratus got around 72mpg. imagine the capabilities of a smaller, say 1.5L turbodiesel hybrid using all the best diesel tech from VW, and all the best hybrid tech from toyota and in a smaller lighter vehicle. 100mpg with today's driving style?

DOH!!! My son started kidney punching me....I had to run to the bathroom and then I was rushed out the door to go and get the food from Carrabbas.

Let me try and find it again. Sorry about that.

Found it!!!

http://www.autospectator.com/modules/ne ... toryid=302

Mike- I know a guy on the west coast that has (2) XT's for sale. I also know a guy down south that has (2) brats that he is giving away. They need to be trailered though. The XT's run and drive.

There are two companies that have recently claimed to have solved the sealing problem of rotary valves. I'd like to picture them with a servo motor on the end and imagine the possibilities. Not as infinitely variable as solenoids for each valve, but a hell of a lot cheaper, reliable, and easier to package if the sealing issue is indeed fixed as claimed. More steam tech. Wonder about flow characteristics through ports. Has to be better than poppet valves. Most established head design knowledge goes out the window so the old timers won't like it.

I have no idea why all hybrids aren't diesels.

Steve

evolutionmovement wrote:I don't know why the Miller cycle isn't employed more often.

I too am fascinated by the Miller-cycle engine. I'm not 100% sure I understand how it works, as every source I've looked at can't quite explain it to me. But it is a very interesting concept.

Unfortunately, it seems to be too expensive to make it worth the R&D. They do have their problems, and while all scientific experiments do, this one wasn't worth working on, I guess.

In all honesty, I do really feel that the boxer engine design is the best we have now for the internal-combustion engine. Now if we can just get it to run on hydrogen

evolutionmovement wrote:I have no idea why all hybrids aren't diesels.

Too much torque. Diesel torque combined with electric motor low-RPM torque?? They'd be breaking all kinds of drivetrain parts

206er wrote: whats worse, is that we are RAPIDLY approaching whats known as peak oil. in other words oil production for a given supply can be described by a bell curve, and we are nearing the peak of that curve for world oil. best estimates are 2008-2011. after that, the supply will begin to decrease while worldwide demand keeps increasing. the economy is basically fucked. and btw this is not a hoax or conspiracy theory.
stuff like biodiesel and kinetic energy is hopefully what will save us.

Not to be argumentative, but this “Peek Oil” biz is bunk, it shows a fundamental misunderstanding of economics and existing technologies. Now I’m not saying oil production wont reach a peek then decline, it certainly will, though I don’t think we will see it by 2011 as we haven’t even used 50% of the know reserves. But the part about the economy being fucked is a bit simplistic at best, its not like the oil is going to dry up overnight, as the supply goes down the cost will go up. There are other current technologies and near future ones that will transition, the real factor is cost, right now oil is cheaper, and by a good margin, when the cost equates with other options they will gain favor. This changeover may lag consumer need and that may cause some pain (mostly in the pocket book). The challenge here (without addressing the political/big business roadblocks) is to identify the near and far transitional technologies and work to have them ready, including production and distribution plans. The bottom line is that the economy will adapt, as will we, some of our now common habits may prove to cost prohibitive in the future… things change.

Something to keep in mind here is that all of this, hybrids, fuel cells, even the internal combustion engine are intermediate, there are two things that will bring us to a sustainable energy state... efficiency, using less energy to do that same work, and getting that energy from truly renewable sources. I think that someday we will have to go directly to the source… the sun.


And as to why we haven’t see diesel Hybrids yet… it’s a mater of marketability, diesel has a bad rap in the US with the environmental types that would by a hybrid, why build a car that nobody will by. But Europe doesn’t share the same misguided view, diesel hybrids will likely prove themselves there and we will take interest when they are getting 100+mpg.

Gary

I disagree. Hybrids originally were only marketed and sold to environmental nut jobs (who else would buy an Insight) and quickly became a reverse status symbol with those who wanted to look like they care for the environment thanks much to Hollywood. Toyota was poised with a useable Hybrid and their sales took off. That may sound cynical, and it is, but I also think it's a good thing. Even if I don't love hybrids, I'd rather people have them than SUVs or whatever other gas guzzling trash being sold and it least people are considering more environmentally sound options. Any tiime you can get people to think is amazing and my hat's off to them for doing so.

But now you have regular people buying these things thanks to gas prices making them socially acceptable and complaining about not getting the stated mileage so they're starting to market them as performance upgrades (because of torque) with a mileage benefit. With diesel they'd still get damn good mileage and wouldn't have to go this route, though they probably still would. I like Subaru's hybrid idea.

As for being too much torque, check out the specs on the new Prius - pretty impressive. They could always downsize the motor to make up for the engine (check out what the original Prius had for torque).

The only big issue with the Miller cycle that I know of is that it requires a supercharger. There are plenty supercharged cars out there, and though they didn't sell many so I probably wouldn't be aware, I don't know of any engine issues with the Mazda Millenia.

Steve

What I understand about the Miller-cycle engine is that the intake valve stays open about halfway into the compression stroke, instead of closing at or around BDC. So yeah, it has to have a supercharger to force the air back into the cylinder through the still-open intake valve against the rising piston. It's a way to get a lot more air into the cylinder than would otherwise be possible. But that's all I understand.

I agree with you 100% on the current status symbol of the hybrid. These Hollywood stars have them to make themselves look good, like they give a rat's ass about anything else but themselves. And while most of educated America knows that's a huge pile of BS, the fact of the matter is, they're still burning less gas and polluting less than if they were driving dubbed H2's, and they're making them more popular for everyday people. It's a dirty way of doing it, but it's working...

And as to why we haven’t see diesel Hybrids yet… it’s a mater of marketability, diesel has a bad rap in the US with the environmental types

I always woundered about that. I hear claims about how environmentaly friendly Diesel engines are. and yet I see diesels running around shooting plumes of black smoke.

How can something that emites so much.... smoke... be environmentaly friendly? Wouldnt that be polution? (not being a smart ass, generaly qurious)

Redlined wrote:I always wondered about that. I hear claims about how environmentaly friendly Diesel engines are. and yet I see diesels running around shooting plumes of black smoke.

How can something that emites so much.... smoke... be environmentaly friendly? Wouldnt that be polution? (not being a smart ass, generaly curious)

Just because its emitting more visibile smoke, doesn't mean its emitting more harmful stuff into the air. Although I would be inclined to think it does anyways.

Spelling fixed.