^ just curious but why doesnt japan allow 3 rotor from factory?

 

I would wonder the same thing... They can sell V12 supercars, but not a 3 rotor?

EDIT:
Looks like the MPG standards for Japan by 2015 will be like 33 MPG for a 3000 lb car, and37 MPG for a 2500 lb car.
Seems like their CO2 approach is based on improved traffic flow and fuel economy more than raw CO2 emission value per vehicle. Not to say they don't test it, but I can't find any data supporting a CO2 maximum requirement.

 

The key then won't be for Mazda to build a more efficient rotary engine but rather build a much heavier car!

 

An mpg requirement *is* a CO2 requirement +/-. Assuming complete combustion, which is a pretty safe assumption, 1 gallon of gas emits ~19 lbs of CO2. (Yes, it weighs more than the 6 lbs a gallon of gas weighs!) http://www.fueleconomy.gov/feg/co2.shtml

 

Not that much of a stretch. A gallon of gas is... 8lbs? 13:1 AFR means ~104lbs of air

 

i thought rotary engines do not respond to increased compression well? bumping up the compression ratio to say 11 to 1 could not really mean much difference? I remember reading that somewhere?

 

I want miles and miles of undulating curves sandwiched between the ocean and the mountains again.

 

^....what? lol

 

it's emission problem.

Something like that, even though Mazda calls it a 1300cc Engine, but the government sees it differently and I forgot the exact math but it was something like that. They would love to release 3 rotor engine, but government saids no,

it might have something to do with the influence from other auto maker as well, but law is law, Mazda can't do **** about it.

 

It's true that traditional Rotary engine with current spark plugs method(location?) does not respond to compression ratio that well. there are gains, just not like "OMG WOW" kind of gains.

One thing for sure is that, while power gain might be small, emission will be much better, and that's probably the MOST important thing to keep Rotary Alive (2nd is MPG, just my opinion)

 

Good points ^ no more spark plug issues, and hopefully flooding as well. I wonder how much of this technology is really under wraps from Hitomi, because he doesn't want other manufacturer's to know of it. Also, rotaries and piston engines are two completely different animals. I am wondering how this technology could apply to both powertrains for efficiency gain. I could understand the rotary, but how much more benefit would this be to a piston engine, as suggested in the article?

 

That is part of my sig, which I wrote. Perhaps a bot trying to provide some useful contribution to the thread? It's got a jpg inserted that I don't care to figure out more about.

 

I honestly don't see how it could be purely the government when the Ferrari 599 for example gets an EPA 15 MPG highway on a V12 engine at 3500 lbs. According to Japan's standards, They should be required to get at least 30 MPG.

I feel that there's no reason that Mazda couldn't improve the emissions enough to have a limited production 3 rotor car or engine option. I think it's more a factor of price point for that limited run, and demand for the engine than simply Japan telling them "no, never again!". If that was the case, Ferrari, Lamborghini, and all the other V10 / V12 manufacturers that get nowhere near "acceptable" MPG would never be allowed to sell cars in Japan.

 

I think it would be cool if mazda started offering "crate" engines like Ford and GM. they could offer several flavors of 13b's, 20b's and 26b's. they may already do this for racing teams, I don't know....

 

13b geometry rotary engines don't respond to changes in static compression with positive results as much as might be preferred.

Mazda has changed the geometry so its a new game

 

Quite true. The "ridge" presented by the center of the chamber housing at TDC presents an obstacle the air-fuel charge has to overcome as it's shoved from trailing side to leading side by the trailing edge of the rotor. The higher the mechanical compression ratio, the narrower the gap through which it can pass.

 

That's also why lots of Japanese cars, including the FD, was forced to retired. for the same reason.

Foreign cars are "exempt" from this "rule", That's why it made Japanese cars look pretty bad back in the days. (limited displacement and Horsepower)

the hp rule was lifted couple years ago, but emission rule stays and much tighter.

 

after 30 something years ...

it's about freaking time for a change!

 

Then why not manufacture/assemble it in one of their new/soon to be new non Japanese plants and import it... Produce the motor in house and ship them complete to the out of country manufacturing entity.

 

doesn't work cuz that means you're "importing" stuff and Japan has very high taxes on import goods (to protect their own local market)

 

I’m surprised the rotary hasn’t been shelved until Mazda can get profitable. They are on the hunt for a strategic partner and I can’t see much in the way of resources being spent on a new rotary engine. I hope I’m wrong but I would think the bean counters would be pounding on the rotary dev teams door pretty hard these days.

 

You're not thinking about the situation correctly. It's not just a matter of profitability. They're setting sales records already this year over last year. Their problem is exchange rate conversions, not their brand's value. If their sales were down 50% year to year, your statement would make more since.

Tax or not, it's a solution to a problem. Large companies don't pay taxes to begin with. They're simply passed onto the consumer. Essentially what you're saying is that the car would cost more off the showroom in Japan than the USA. That's all.

Here's some info on just how easy it is / would be to import to Japan... Not trying to argue to be an ***, I just find that most of the excuses as to why they couldn't build a 3 rotor, if they actually wanted to, or if there was a market to do so, to be complete BS.
http://www.thetruthaboutcars.com/201...port-barriers/

 

n/m

 

how has the geometry changed--do we know for sure?

 

Not specifically. He said 'shape', which implies geometry, but does not confirm it. 'Shape' could be anything from rotor spin path to housing shaping to eshaft changes to compression cavity differences. Or all of the above.