Pratt & Whitney power outputs

[tallguy]

While the R-1830 was developed to 1200hp by 1939, AFAIK the R-1535 and R-1340 maxxed out at 800hp and 600hp.If they had been developed to the same power to displacement ratio, they should have been good for 1000hp and 900hp respectively. Does anyone have info on efforts to increase power in these engines? Were there any design differences that would have precluded increased power, or is it simply a question of perceived lack of need?

 

[tallguy]

While the R-1830 was developed to 1200hp by 1939, AFAIK the R-1535 and R-1340 maxxed out at 800hp and 600hp.If they had been developed to the same power to displacement ratio, they should have been good for 1000hp and 900hp respectively. Does anyone have info on efforts to increase power in these engines? Were there any design differences that would have precluded increased power, or is it simply a question of perceived lack of need?

Still interested in info on this

 

[Pasoleati]

Good question! The closest rival R-1820 was developed until the final variants produced 1525 hp and even wartime variants over 1400 hp.

 

[fortrena]

I seem to recall coming across one or more mentions of a 1,000-hp and 100 octane version of the R-1535 Twin Wasp Jr. engine which was to be fitted with a two-stage supercharger. Given the limited power and growth potential of that version, and possibly some reliability issues with the R-1535 itself, it was never put in production. Indeed, I cannot recall if that engine was even tested. That high altitude R-1535 might have been initially considered for use on the Grumman XF5F Skyrocket twin-engine carried based fighter.