I have a 18' Campion w/ aluminum 3 blade 21p x 14.25'' and @ WOT I get 4400 rpm ( 3800-4200 suggested) at a top speed of 48 mph. If I were to go to a SS 4 blade how much pitch would I need to drop to and still keep my 4400 rpm? I'm hoping a 4 blade will give me better fuel economy at cruise!
I have older 1979 470 and would like to change out the exhaust manifold and riser to the newer aluminum version. Can anyone tell me what problems I will run into before I spend any money on new ones. I'm doing it for weight savings, but wonder if the newer style ones flow better!
Do all 3.7L mercruisers share the same camshaft? It seems there are alot of different ideas on the powerband of this engine. Mine is a 1979 470 and says 3800-4200rpm on the valve cover and some people say 4200-4600rpm ??? New to 3.7L's
