Actual Rotary Displacement Request

Libor · 05-31-2011, 04:41 PM

What is point of this? It doesn´t matter if someone calls 13B 1.3L or that its comparable to 2.6L 4 stroke engine or when whole engine is used it equates to 3.9L. All three variants are correct, but only last is fully understandable.

First variant is good for manufactures to simply describe engines configuration.

No one would argue that power equates work per time. Discussed engines are positive displacement pump. So what will happen when you rotate 13B and any 4 stroke 2.6L for same number of revolutions? It pumps same amount of air - granted with same VE%. So they are fully comparable - no handicap. I can´t recall any sanction body which would use this true equalizer - SCCA IIRC classed rotaries with 1.7 multiplier - probably lower thermal efficiency was taken into account... Or BK motorsports effort in ALMS - Courage C65 with 20B - class allowed for 3.5 atmo engines and intake restrictor. They were allowed although 20B equates to 3.9 and also were permited to run larger restrictor. So there isn´t any handicap, exactly opposite - sanction bodies are kind enough, to account for wankel engines disadvantages.

But only last one is really true, it takes 3 revolutions but all parts of engine went through all cycles and everything adds up.

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05-31-2011, 04:41 PM	#6
Libor Rotary Fan in Training Join Date: Aug 2010 Posts: 54 Rep Power: 16	What is point of this? It doesn´t matter if someone calls 13B 1.3L or that its comparable to 2.6L 4 stroke engine or when whole engine is used it equates to 3.9L. All three variants are correct, but only last is fully understandable. First variant is good for manufactures to simply describe engines configuration. No one would argue that power equates work per time. Discussed engines are positive displacement pump. So what will happen when you rotate 13B and any 4 stroke 2.6L for same number of revolutions? It pumps same amount of air - granted with same VE%. So they are fully comparable - no handicap. I can´t recall any sanction body which would use this true equalizer - SCCA IIRC classed rotaries with 1.7 multiplier - probably lower thermal efficiency was taken into account... Or BK motorsports effort in ALMS - Courage C65 with 20B - class allowed for 3.5 atmo engines and intake restrictor. They were allowed although 20B equates to 3.9 and also were permited to run larger restrictor. So there isn´t any handicap, exactly opposite - sanction bodies are kind enough, to account for wankel engines disadvantages. But only last one is really true, it takes 3 revolutions but all parts of engine went through all cycles and everything adds up.