looks nice .
No experiance with the Fox Eagle , but a Merco 49 . With This intake . the Trumpet ish one . But the long lug case , single plug , & a 49 not a 61 . Tho Ive two 61s now , & no 49s .
Incidently , theres two C'Case Intake bore diameters . Bored one of the 61s to the 1/2 bore Of the Trumpet intake .
The 49 was initially a bit tight , but loosened of & on the Fox Fuel , 27 % oil , 15 & 20 % Nitro , with stock head clearance , ran superbly . Even when you put a muffler on it .
o.k. I was out in the sticks .
The big heavy ugly Super Tigre Quite Muffler, it ran well . No power loss . tho snapped the puny 6 B.A. bolt aft , doing squares .
Stock Head Clearance . Australia . Might be ' Nitro ' Comp Ratio for Here ? .
Windsor Wood 12 x 6 , thinned . on the 72 Oz 72 Span Mew Gull . tho'd be more with 4 Oz. muffler !
SO , think a GOOD Merco ( This was as new ) would be dependable & trouble free .
Had the tourque to hold a steady speed , even when it was blowing . Something Id think youd need . As theres a bit of frontal area having several wings & suchlike .
NEEDS GOOD COOLING FLOW , a decent intake area and free flowing cowl discharge . Mine was 7.5 mm intake bore. Will dig out the timing figures . they Vary .
Was a round hole to passage in crank , whereas the 61s I have are rectulinear . One 61 has a 1/4 prop thread/ shaft . & its shorter nosed than the usual 5/16 thread shaft .
I suppose a Merco Muffler would even fit .
Was much gruntier & steadier , rich , with the Nitro . So 10% might be the idea . Ran a steady ' top of ' the four stroke , puled uphill well .with the weight .
Good in the Squares , would stay ' fueled ' . Probly a 6 Oz / 150 c.c. fuel tank .
p.s. Hope youve got a good strong ' no slop ' control system . 1/8 wire ( 3.2 m.m. dia. ) horn wire etc . Plus the 4 inch bellcrank . for leverage . Even a 4 1/2 " bellcrank ! .