RE: 1.08 o.s. fuel tank
i think you'll have no problems with that setup...imho, muffler pressure is the key...one of my engines is an os.37szh, mounted on a 10 pound heli...the carb has a 10mm bore...despite having a main tank, header tank, and lots of fuel line, fuel flow is amazingly constant...the engine uses high nitro, runs at high rpm, and is set a little on the 'fat' side...once, the muffler pressure line had an air leak at the muffler nipple...the engine leaned and quit...with that kind of experience, i've never had to use a perry pump on my planks although using a pump might improve fuel flow even more...ken