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Chickenman

Oct 3 2009, 12:47

QUOTE (cheapracer @ Oct 1 2009, 14:33)

Your still confused,

At 9000 rpm the Rotary engine is completing 9000 firings which means it is completing 9000 thermodynamic cycles - how else could it fire 9000 times? (per rotor housing of course). It's true that the rotor is turning 3000 rpm if you disclude the fact that the rotor isn't revolving around a fixed axis. Does anyone know what you call that by the way?

Oh it's an orbital revolution apparently! Now why didn't Ralph use that one?!

Per single turn of the crankshaft of a Rotary engine you get one firing. A Rotary's design and layout doesn't allow for the equation of 3 crankshaft turns for 1 firing in the real world - it may just not run! It has a Reuleaux triangle shaped rotor in a epitrochoid shaped housing for the purpose of actually functioning as a whole, not a third.

Anyway, People can decide for themselves...

Crikey...that makes me dizzy!!

cheapracer

Oct 3 2009, 15:37

QUOTE (gruntguru @ Oct 2 2009, 07:21)

Sure people can decide for themselves but they will be either right or wrong.

QUOTE (gruntguru @ Oct 2 2009, 07:21)

Of course that rotor has fired 3 times - it has 3 chambers!!

and thats the point - it's designed as a whole that way, not as a 'three cylinder' as we relate to a piston engine.

Before a person can decide for themselves they need to make and understand that distinction.

gruntguru

Oct 3 2009, 23:50

QUOTE (cheapracer @ Oct 4 2009, 01:37)

and thats the point - it's designed as a whole that way, not as a 'three cylinder' as we relate to a piston engine.

Of course not - its a "three lobe" rotor. It can also be designed with a different number of lobes. Since you are suggesting that the capacity of a 3-lobe Wankel is equal to the air displaced in 1/3 turn of the rotor, I guess the capacity of a 4-lobe Wankel is equal to the air displaced in 1/4 turn of the rotor etc?

Have you read this book? Wankel History

The fact is, that a full cycle of the engine takes one rotation of the rotor and during that time all chambers will have completed one cycle only. One rotation of the rotor completes 2 cycles of the PV diagram ie 1 four-stroke cycle. Rotational speed of the output shaft is quite incidental to the thermodynamics of the engine.

cheapracer

Oct 8 2009, 09:20

I was just interested to read that Ford were considering using the Rotary in the Falcons to race at Bathurst in the early 70's. It was to be called the Rotary HO.

Grumbles

Oct 8 2009, 09:59

QUOTE (cheapracer @ Oct 8 2009, 10:20)

I was just interested to read that Ford were considering using the Rotary in the Falcons to race at Bathurst in the early 70's. It was to be called the Rotary HO.

That was spectacularly bad...

I lol'd.

gruntguru

Oct 8 2009, 11:34

QUOTE (cheapracer @ Oct 8 2009, 19:20)

I was just interested to read that Ford were considering using the Rotary in the Falcons to race at Bathurst in the early 70's. It was to be called the Rotary HO.

That is hilarious on so many levels.

Wuzak

Oct 8 2009, 23:33

Not quite as amusing, but Mazda did fit a rotary to an HQ/HJ/HZ Holden and called it the Roadpacer.

http://en.wikipedia.org/wiki/Mazda_Roadpacer_AP

cheapracer

Oct 9 2009, 04:00

QUOTE (Wuzak @ Oct 9 2009, 07:33)

Not quite as amusing, but Mazda did fit a rotary to an HQ/HJ/HZ Holden and called it the Roadpacer.

http://en.wikipedia.org/wiki/Mazda_Roadpacer_AP

Yup, I first saw that in my 1974 World Cars Book in 1975 which I still have and treasure.

Did you know it had a torque converter in between an otherwise standard flywheel and clutch (manual 5 speed)? The converter was fed from the engine oil.

Wuzak

Oct 9 2009, 04:01

QUOTE (cheapracer @ Oct 9 2009, 07:00)

Nope, I did not know that.

Did it help?

gruntguru

Oct 9 2009, 06:11

QUOTE (Wuzak @ Oct 9 2009, 14:01)

Nope, I did not know that.

Did it help?

I'm sure it reduced the number of clutch replacements per hill-start.

Catalina Park

Oct 9 2009, 08:47

QUOTE (cheapracer @ Oct 9 2009, 14:00)

At the same time that Mazda was selling the Holden Premier as a Roadpacer in Japan, Isuzu was selling the Holden Statesman as an Isuzu Statesman.

I recall an engine builder in NSW Club Car (now Improved Production) races in the late 80s that was running a torque converter + five speed manual in a reasonably quick car.

cheapracer

Oct 9 2009, 10:29

QUOTE (Catalina Park @ Oct 9 2009, 16:47)

.

I recall an engine builder in NSW Club Car (now Improved Production) races in the late 80s that was running a torque converter + five speed manual in a reasonably quick car.

Plenty of them came to Oz through importers in the 80's. Nicknamed the "TQ 13B" - apparently common to the RX5 in Japan. I plugged a few up, 1 oil feed from the back of the crank and a return into the rear housing through a dowel if I remember correctly.

I convinced a friend to run one in his RX4 speedway car (13B PP) and it was competitive as it was easy to keep up the revs coming off a corner with the 1000 odd rpm jump but oddly it broke 2 crankshafts and we could only put that down to the TQ doing something strange so he went back to standard.

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