Actually, if you cannot see the hole, it will work fine. I've flown the redhead, front intake McCoy 19 in CL stunt a good bit and really like them. Mine have Super Tigre NVA's in them, because they came (used) without any NVA. I fly them on Sig Champion 10% nitro, 20% oil, half castor, half synthetic, with an APC 9 x 5 prop.