rotarygod

Ash8 actually let me know about the link so it may very well already be posted somewhere and I just missed it. In the event that anyone else did too, here's a little tidbit from Rotary News about the dimensions of the 16X.

http://rotarynews.com/node/view/1050

chiketkd

iTrader: (5)

Good stuff! Thanks for the link RG!!!!

RIWWP

iTrader: (2)

Very very interesting. The rotor width information in particular, and it makes sense as a point of fuel waste for the RENESIS.

It is also encouraging that they filed for the patent in April of 2009, so the poor economy isn't halting their stride for it. Maybe delaying, but certainly not stopping

The_Beast

I always thought the rotors looked too wide too. I'm no engineer or expert at rotaries by a long shot, but just by common sense it would seem that to make it not as wide, it would let it rev faster, higher, and cut consumption. So far, the 16X seems like it might be what the rotary world needs.

Jedi54

iTrader: (7)

excellent link!

rotarygod

The 16X rotors are the same width as a 12A.

RIWWP

iTrader: (2)

RG: Is there any reason you would see to why they increased the width? (other than mis-information or assumption)

rotarygod

They didn't increase the width. They decreased it 10 mm. Then on top of that the rotor gained height which makes the width even more significant.

RIWWP

iTrader: (2)

Sorry, I was referring to the change from the 12A to the 12B.

rotarygod

It was probably pretty easy to just make things wider as the end housings didn't have to change nor did the eccentric shaft offset. It was merely a 1 dimension change as opposed to all of them. The 10A also had the same eccentricity and rotor height but had 60 mm wide rotors.

rotarygod

As some people know, I am a pretty big train buff. In fact it is my largest hobby with the rotary taking a close second. I'm particularly fond of steam engines and their design. I came across this quote about steam cylinders. It directly relates to why the "bore" of the 16X (rotor width) is less and why the "stroke" is greater.

"Long stroke small diameter cylinders have a number of advantages, such as lower clearance volume, and lower heat transfer losses. The objection to them was poor "breathing" and balancing difficulties. Both of these can be overcome."

Breathing and balancing aren't going to be an issue in a rotary but the first part is absolutely relevant. Mazda even stated that the 16X wasted less heat due to the change in dimension. Here's proof of that in 200 year old technology. If you could measure the amount of surface area along the walls and rotor faces in the combustion chamber as the engine rotates, you'd see that the total area is less than in an engine with the same displacement that has a wider but shorter rotor. I am curious what exhaust temperatures will be like. Less heat loss to the cooling systems implies more heat out the tailpipe although not necessarily.

DubbsLuvs8s

iTrader: (1)

I love technical jargon

RIWWP

iTrader: (2)

Huh. Cool. Interesting to find out those temperatures. If it is high pipe temperatures, that would greatly reduce cat life, and cause a need for heavier shielding? More heat resistant shrouds as well.

Mazmart

iTrader: (12)

Or would it equal less heat in the exhaust and cooling system and more power/displacement.

Paul.

rodjonathan

iTrader: (6)

great link

Mazmart

iTrader: (12)

For the record, I don't have 1/3 of RG's scientific mind.

Thanks for the article. It is good. I was of the opininon it would be 70mm with 13A eccentricity and I did see the US patents a few months back I believe.

Paul.

zoom44

as did i paul

Huey52

iTrader: (2)

That's what I was thinking Paul. A component of the "greater efficiency" the 16X promises to bring to the table.

j_tso

I quoted this in the other thread
My (uneducated) theory has always been that the main problem with RE combustion was the rectangular combustion chamber and since a spark plug (combustion, actually) is elliptical, so thinner rotors would have a more complete combustion.

Nopstnz

WHY THE HELL AM I SEEING NOTHING ABOUT POWER OUTPUT! all i see is greater fuel efficiency blah blah blah. I swear to god if mazda releases this engine with the near same power output of the current renesis I will blow an apex seal.

rotarygod

I would guess that a production version, assuming we see it, would be around 275-280 hp or so but with the potential left in it to hit 300. The engine is 30% larger. Since the larger engine will have a lower redline, we can't directly say that it will have 30% more power. However since direct injection and the new combustion chamber shape increase efficiency, the lack of rpm may be made up by the efficiency gain in terms of power. It all depends and as of yet we don't know what the redline will be. If the Renesis puts out an honest 225 hp, regardless of what it's rated at on paper, then just using a 30% size factor as a guide, that would put the new engine at 292 hp. Alot of assumptions in there. Mazda may detune it a bit for economy and emissions but the ability to hit 300 hp doesn't appear unreasonable. Torque will probably be about 190-200 ft lbs or so. This is all a guess of course.

jones75254

iTrader: (2)

^Because HP isnt going to be a dramatic increase, and as fuel economy appeals to the masses, thats what they are going to focus on in the articles. Above all, they need the car to actually SELL to keep the rotary alive. As long as the weight is kept under 3000#, it should be fine...considering it has the 270'ish hp people are predicting. Im guessing with the 16X the car will have 0-60 in low to mid 5's, 1/4 mile in the high 13's. Expecting more from an NA 1.6 Rotary would be asking alot (unless car gets dramatic weight loss). Just guesses (..or perhaps hopes?) so dont go gettin all froggy.

...and those #'s would be jsut fine and dandy with me BTW

renesisgenesis

If the 16x has a lower redline I will personally attack mazda headquarters with lethal force.


but I am a rev ***** so there you go.

rotarygod

^Prepare to attack! They've already said the redline is lower. I personally support a lower redline on a street car as that means a wider powerband.

rotarygod

Don't sell yourself short Paul. You're a freaking genious. Then again as long as there is a Rick Engman in the same building, no one else really needs to know anything!