"FLIGHT" MODEL/ ZY HOBBY JAPANESE ZERO 91 INCH WS Cowl Diameter ?
 

Does anyone know if a Saito 84cc Radial or an Evolution 77 Radial will fit under the cowl ?

The other "zero"s available in this size class use them. The Top Flight Zero can run a Saito 60cc Radial an 84cc radial with mods. The Top Model 93 inch Zero can run a Saito 84cc radial with no problems under the cowl.

Unfortunately I have not been able to locate cowl diameter reference for the Flight Model/ZY hobby

thanks