Old 80 rigger

[normlee]

A buddy of mine bought an old rigger with a cmb 80 gold head. Can anyone please suggest a prop to get it going?

Norm

 

[Danny King]

H48 if it's a strong motor. H32 will run but a smaller prop. A 1470

 

[Greg Wannamaker]

Best to check with your buddies in your neighbourhood, so many variables are wrapped up in what prop your boat will pull, the hull you have, overall health of your motor, set up, pipe used, cable used, prop bore, average temp/humidity. Assuming your using 1/4" bore props, pick an average pitched H32, getting it running clean, find your max rpm and speed you can coax out of it, then start experimenting with props and pitches to find the sweet spot , the exact answer is different for almost every boat. Your running buddies should be able to point you in the right direction the quickest.

Enjoy testing!

 

[Ray Sametz]

My old 80 Mongoose was strolling this year with a H-38, Dia. 2.470 Pit. 4.10 Cup 4.5. AB Quiet pipe @ 11-5/8. 1500 feet above sea level.

 

[bermudadude]

depends on what gold head.

the original EVO gold heads--->>those engines like to be loaded.

an H38 with 5" cup,,,a 63-64mm 1667

tho youve got to have that cmb "fat belly" 67/80 pipe. thats the combo.

if its the "cam"(drum)(newer) engine........meh....its gonna need the newer piston/sleeve/head button. and even then its a mechanics job because the stroke/rod is different length. then try h32,h38, any stock or slightly under 5" cup 62-64mm prop

 

[normlee]

Thanks, that should get us going

 

[bermudadude]

actually u never said what boat it was.

if its that old then even the "x" series octuras will work. 465,467,665 ...

i forgot 1465,1467