AHC: no RR Merlin

British companies were sometimes licensing French and German engines, so licensing US engine might not be such a stretch.
Works for me.:)
The R-2180A (pre-war engine) is a really misteroius engine - yes, we know the 'hard' data (bore, stroke, HP, rpm) but the 'soft' data is as good as not available, like the reliability. Just by looking at cubic capacity and power, it might be a good choice.
I do like the "off-brand" feeling from it, so I'd be inclined to use it.
The Buzzard was already a big enough engine, 36.7L, so the dispalcement can remain as-is. RR have had good superchargers even before Hooker arrived, obviously Hooker will improve it still. Carb - use the 'injection carbs', not the 'float carbs'.
I'm happy to leave the displacement alone, then, & I've been presupposing "best practise" on carb type selection. My thinking is, tho, none of the a/c engine makers seemed to use enough carbs, & that's an obvious chokepoint for power. The other option is reducing friction, which implies early discovery/development of *Teflon, which seems less likely.
 
When an engine is being fed by a supercharger you don't need lots of carburetors. The French Hispano V12s are the only engines I can think of that used multiple carburetors and they weren't exactly pulling up tree stumps compared to equivalents.
 
The R-2180A (pre-war engine) is a really misteroius engine - yes, we know the 'hard' data (bore, stroke, HP, rpm) but the 'soft' data is as good as not available, like the reliability. Just by looking at cubic capacity and power, it might be a good choice.

think of it as half a Wasp Major, with the pre-war P&W design feature set
 
When an engine is being fed by a supercharger you don't need lots of carburetors. The French Hispano V12s are the only engines I can think of that used multiple carburetors and they weren't exactly pulling up tree stumps compared to equivalents.
It's all about airflow, tho. A single carb can only flow so much, pressurized or otherwise. More carbs means more airflow. Quite aside issues of fuel mixing.
 
When an engine is being fed by a supercharger you don't need lots of carburetors. The French Hispano V12s are the only engines I can think of that used multiple carburetors and they weren't exactly pulling up tree stumps compared to equivalents.

Soviet V12 engines, Klimovs and Mikulins, used multiple carburetors, too. Talk about restrictor to the airflow...

It's all about airflow, tho. A single carb can only flow so much, pressurized or otherwise. More carbs means more airflow. Quite aside issues of fuel mixing.

As fast said above - only one carb if it is before S/C stage. Just move away from float-types ASAP.
 
As fast said above - only one carb if it is before S/C stage. Just move away from float-types ASAP.
Unless aeroengines are very different in ways I don't understand (& not impossible, by any means;)), that's contrary to everything I've seen: more carbs (to a limit) always improves performance, & mixing fuel & air in/through the blower is a bad idea; putting the carb downstream is preferred.
 
Unless aeroengines are very different in ways I don't understand (& not impossible, by any means;)), that's contrary to everything I've seen: more carbs (to a limit) always improves performance, & mixing fuel & air in/through the blower is a bad idea; putting the carb downstream is preferred.

Problem is with a Radial, when you have 14+ individual cylinder heads to feed, you would need a crazy number of carbs, and the headache of trying to sync all them.

Here is some info
https://books.google.com/books?id=rrdsBwAAQBAJ&pg=PA119
 
Problem is with a Radial, when you have 14+ individual cylinder heads to feed, you would need a crazy number of carbs, and the headache of trying to sync all them.

Here is some info
https://books.google.com/books?id=rrdsBwAAQBAJ&pg=PA119
Hey, I'm not saying it's easy or simple. Radial designers figured out how to run carbs & feed the beast; all I'm saying is, replicate that a time or two (or five, or whatever). Better still, use fuel injection.

Thx for the link, btw.:)
 
Unless aeroengines are very different in ways I don't understand (& not impossible, by any means;)),

With WWII engines it wasnt the fuel supply that was important it was how much air that you could shove into the cylinders that counted. A very late war 100 series Merlin engine was producing 2,200hp @3,000 rpm using an Injector Carb not too different in size to a 1937 Mark III Merlin producing 1,000hp @ 2,850 rpm.

Its the blower not the fuel tap (spigot for you colonial chaps ;)) thats important
 
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