I roto i te tīmatanga o te 1937, ka whakahau te USAAC Curtiss ki te urutau i tetahi P-36 ki te hou engine Allison V-1710 turbo-supercharged wai-whakatika ki 1,150 hp (860 kW). tohua Curtiss XP-37, whakamahia te rererangi te tauira taketake 75 airframe ki radiators whakairi i runga i nga taha o te fuselage a tawhio noa te engine. nekehia te kokopi tawhiti ki muri ki te hanga i te wāhi mo te radiators me te turky pūnaha bulbocharger, me ki te toenga o te waka rererangi. rere te waka rererangi i Aperira 1937, tae 340 mph (550 km / h) i 20,000 ft (6,100 m). Ahakoa ko te turbo-supercharger tino kore pono, me te kitenga i te kokopi i runga i te takeoff me te taunga i tata kore, i whakaaria e te USAAC nui faahiahia e te 13 turbo YP-37 ki te whakamātautau i te ratonga, me te rere i te utu o te pūkaha Curtiss XP-37.
Ko te tau 1939