Rolls Royce Crecy

Adam Weiss

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I just watched an interesting video about this engine and its development during the war.
Very impressive technology and performance for the time.
This was a 26L V12, producing more than 2500hp.


Wikipedia had a little more information about it:
https://en.wikipedia.org/wiki/Rolls-Royce_Crecy

These numbers got me wondering.
Why not make a V-twin version today?
Based on the V-12 numbers, a 4.3L (264 in^3) V-Twin could produce 450hp on 14gph 100LL, and weigh 316 lbs or so.

This engine was direct-inject w/ turbo, and seems to produce better numbers than today's aircraft engines.
With only a V-twin, the gearing would be much simpler than the V-12.
I know absolutely nothing about engine design, but it sure seems like it's doable...and desirable.
 
A 2 cylinder with the same architecture would have a pretty long interval between power strokes. Gut feeling is it would take a V-4 at minimum.
 
A 2 cylinder with the same architecture would have a pretty long interval between power strokes. Gut feeling is it would take a V-4 at minimum.
What does that imply? High vibration?
Also, it’s a 2-stroke, so wouldn’t the interval be similar to a 4-trike 4-cylinder?
 
Aircraft Engines (albeit jets) killed Rolls. They persist only because VW took over the remains and kept it alive.
 
I just watched an interesting video about this engine and its development during the war.
Very impressive technology and performance for the time.
This was a 26L V12, producing more than 2500hp.


Wikipedia had a little more information about it:
https://en.wikipedia.org/wiki/Rolls-Royce_Crecy

These numbers got me wondering.
Why not make a V-twin version today?
Based on the V-12 numbers, a 4.3L (264 in^3) V-Twin could produce 450hp on 14gph 100LL, and weigh 316 lbs or so.

This engine was direct-inject w/ turbo, and seems to produce better numbers than today's aircraft engines.
With only a V-twin, the gearing would be much simpler than the V-12.
I know absolutely nothing about engine design, but it sure seems like it's doable...and desirable.

Engines don’t scale down like you have posted. As they shrink they get heavier per HP produced for a variety of reasons. A two cylinder with a 450HP output would also need a tremendous amount of counterweights and other means to reduce vibration and would be incompatible with most if not all propellers currently produced.
 
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