jeff_rx7

iTrader: (1)

i have recently come across for the third time the 13b refered to as a 2.6L? can somebody clarify this for me?? thanks

Turbo II

iTrader: (1)

We have a 1.3L rotary engine that is equal to 2.6L piston engine.

Carzy Driver

13b = 1.3l
20b = 2.0l
26b = 2.6l

classicauto

iTrader: (3)

26B - four rotors comin' at ya~!

sleepydave

we have a power stroke every 360 degrees of crank/eccentric shaft revolution vs a 4stroke piston motor taking 720 degrees to make a single power stroke.

Icemark

In Europe and most racing bodies, they double the displacement of the rotary engines for classification. Hench a 13B would be 2.6 litres in Europe or IMSA racing, even though it is technically a 1.3 liter motor.

Its to make the rotary motor less compeitive when compaired to piston motors as the rotary engine is more reliable and more powerful than engines of the same actual displacement.

13b4me

I think it's funny... Piston guys call our motors "inferior", yet they have to make special rules to class our engine size...

particleeffect

can you not count or something? it's the SAME reason 2 stroke engine classes started allowing 4 stroke engines with double the displacement.

4 stroke piston = 1 power stroke per 720 degrees.
rotary = 2 power strokes per 720 degrees.
2 stroke piston = 2 strokes per 720 degrees.

so to spell it out for those of you who are really dense: we pump 2x our "mazda displacement" in a 4 stroke piston cycle. jesus, it's not a hard concept. it isn't some arbitrary idea to level the playing feel or make up for how super awsome rotary engines are, it's based on what you do per revolution.

if you wanted to classify 4 stroke piston engines by "rotary terms", or per 360 degrees, gues ******* what? they'd be half the displacement too! ****, then they'd be way more advanced because they'd be making way more power per liter right?

Phantomkid

Everyone is going into piston enegine as one power stroke per 720 degrees. It actually takes 720 degrees to complete its cycle on any piston engine. And you can find out how manydegrees each power stroke happens in 720 degrees by dividing 720 degres by the number of cylinders. a 4 cylinder has a power stroke every 180 degrees in 720 degress. and a 8 cylinder has a power stroke every 90 degrees in 720 degrees. every cyclinder should have a power stroke by 720 degrees

Phantomkid

hmmm you guys are correct if your talking per cylinder totally over looked that my bad

13b4me

Look ***... I don't care how you break it down, the ambient displacement of a 13B is 1.3L... I don't give a **** what the cycle entails, because that's just the advantage we have over everyone else... Sorry their engine design isn't as efficient as ours...

Just like the 787B won the 24HR @ LeMans OVERALL and the next year was BANNED because it was too competitive, even though it was running against cars equipped with V12's... I don't wanna hear that BS about "rotaries pack twice the air per revolution" because well... That's just the superiority of the design for you...

rotary emotions

For once and for all: the ONLY reason they doubled the capacity (which IS mathematicly 1.3l for a 13B) is MONEY. Rotary engines were invented in Europe, and we pay a lot of taxes on cars. So when NSU had this 1.0l engine putting out 115hp, they had to do something about it. Racing rule-makers follow the twice-the-powercycles idea, to level out the difference in output. This is somewhat logic, since indeed rotary engines have three faces on the rotor, each having their OWN combustion chamber. So one revolution of the rotor puts out three power strokes. Since there's a 3 to 1 gearing between rotor and E-shaft, that makes 1 powerstroke for every rev of the E-shaft. Of course multiplied by the number of rotors, as you'd multiply with the number of pistons.
For Le Mans (the 787B) the FIA used a number of 1.8x rotary displacement (making the 26B equal 4.8l, opposed to Jaguars 7.0l V12), as the 2x didn't seem that realistic after all.
To put things clear: the displacement of a 13B IS 1308cc, but equals (more or less) 2.6l of a conventional engine. This also how it's officially stated overhere by the lawmakers. They always have the engines stated as 2 x 654cc equals 2.6l. And my 12A is OFFICIALLY a 2.3l engine, making road taxes almost 3x as expensive as if it was a 1.2l...

13btnos

iTrader: (1)

Sorry but there are only 2 combustion chambers in a 13B. I understand what you mean but any which way you say it it is still a 1.3 liter engine and there are only 2 combustion chambers in a 2 rotor rotary engine, and that would be where the plugs are and where the power stroke occcurs. If you compare it to a 4 stroke motor it is 2.6 liters and if you go further and count the complete cycle of all six "chambers" you will get 3.9 liters of displacement. Any whooo whatever. This **** gets old. I just look at the engine and say damnnnn that little *** engine can sure put out some horsepower. Who cares what the displacement is.

TEZTnTUNE

the best way to look at it is your engine is a 1.3L but it flows air like a 2.6L. on another note no the rotary engine is not that efficent. if it were every oem would use them. if u know your rotary history youd know that others have tryed( gm and mercedes). all found the engine to be inefficient and unreliable. in a nutshell u have shitty combustion chamber design. even shittier mechanical advantage. the renesis is a good step forward in the right direction

lastphaseofthis

iTrader: (8)

Toyota is now working on there own rotary engine powered car project, only time will tell

13b4me

There were others as well who tried and failed... MANY... Ford even attempted a rotary Mustang... FUEL efficiency is the reason it never took off...

As far as a rotary being innefficient... They are VERY mechanically efficient... Thermal efficiency is where they lack greatly, being they produce so much heat for an engine of their size... Otherwise they are greatly superior to just about everything else out there...

rotary emotions

Ford didn't really try a rotary Mustang, Curtis-Wright did
For those still staying they all failed on reliability: that's BS! ALL rotary projects failed on fuel consumption, only GM's engine failed on GM's stupidity. When the licences were sold by NSU/Wankel, all buyers had to share knowledge. All, except one: GM. They had been able to get a more expensive exlusive license, due to them being the worlds biggest at the time. One of the mistakes they made was that they didn't wan't to share their experiences, but therefor ended up not being able to look at other efforts (Curtis-Wright in the USA) and take advantage of those.
So they build a all-iron engine that was soon very heavy aswell as very bad: housing warped.
All other factories build prototypes, and later rather good engines ( Mercedes-Benz build some really serious stuff) but most were peripheral port. This makes the engines very thirsty, as there is a large overlap between intake and exhaust opening times (as if both valves would be open together in a piston engine). The Renesis is the first to finally go back to original ideas of using side intake and exhaust. In the sixties most rotary builders knew this was the way to go (the design of the renesis is not at all revolutionary) but materials couldn't hold the heat.
So when the fuel crisis came in the seventies, nobody wanted a thirsty engine anymore.
The talkings about unreliable engines are all caused by a myth created around the NSU Ro80, which wasn't a bad engine either, but was too complicated for those days mechanics. Of all engines changed under warranty over 80% was good! Engines were changed for several reasons (mainly carbs or ignition) that didn't have anything to do with the engine itself.

TEZTnTUNE

last time i checked fuel comsumption was a direct link to efficiency. thats why guys with alot of roatary knowledge seem to avoid the bsfc of the rotary. and no they are not mechanically efficient at all. u really want to get into a meaningful discussion lets talk about mechanical advantage. u know what that is 13b4me?

TEZTnTUNE

ill believe a toyota rotary when i see one flooded in someones drive way

13b4me

Ok sure why not?

The standard piston-driven ICE has multiple cylinders working on different strokes at any given time... Not to mention they EACH must come to a complete stop before they can turn around and go the other way... This means you have anywhere between 3-12 pistons that are fighting against each other constantly... And this is mechanical advantage?

The rotary on the other hand, is moving in the same direction AT ALL TIMES, which means far less drag required to operate, and leads to a very smooth curve throughout the powerband... Mechanical advantage is definately NOT what the rotary lacks... It requires far less lubrication (think that might be a clue?) to operate, and is mechanically efficient to a degree that piston engines will never attain...

Do a little research before you call me out next time buddy...

TEZTnTUNE

u seem to be very one dimensional in your argument. u are correct to a degree but you seem to leave out a few chapters on that book. how about torque production and mechanical advantage? after all isnt that the name of the game? i thiknk u left that part out of your statement. the stroke and rod length of a piston engine will affect its MA in relation to its torque output. now u apply the same info to a rotary and u start to understand a bit of why they move air like a 2.6L but doesnt make anywhere near the torque of one.
wasnt calling anyone out i never do that. just asked if u knew.

classicauto

iTrader: (3)

doesn't torque output also have alot to do with mass more so than mechanical advantage?

I.E. the piston motor of 1.3L displacement has a heavier rotating mass and therfore the larger mass translates through the driveline as more torque..

the rotary on the other hand would have a lighter mass turning the driveline and thus less torque...

am I way off base because I was under the impression of what I state here more so than these other ideas....I am genuinely asking - not trying to faceslap here

edit: and also wouldn't distance from the center of rotation have alot to do with mechanical advantage more so than simply just design...

something like using a longer handled rachet, the piston motor is "wrenching" on the crankshaft with a longer handle than the rotary....doesn't that play in to the torque factor as well?

TEZTnTUNE

i believe its one of the factors ina certain design yes more important? dont know at least i dont think so. but it all goes to my point. are our rotary engines truely more efficient at producing power?

13b4me

The rotary isn't designed to produce large amounts of torque though... It's designed to reduce the frictional drag and resistance, so it revs quick, and produces more power up top... The arguement here isn't even about whether the rotary is a better engine or not... That's been beaten to death so many times, I don't even care to speculate...

The issue here, is whether the 1.3l rotary should be classified as a 2.6l, when the ambient displacement of the engine is 1308cc... And I think it shouldn't...

TEZTnTUNE

well u were saying how efficent the engine was compared to a piston engine and i disagreed with that poiint. but i dso agree that its a 1.3L not a 2.6L but it flows like one but doesnt make the torque like one. and thats where mechanical advantage comes in to play. i think the number one flaw with its design is its combustion chamber. where the hell are my 14 to 1 compression rotors at huh??? the frickiin' honda guys have it why cant I??????