CAN ANYONE TELL ME HOW MERCRUISER RATED THEIR UNITS IN 1984. WAS IT AT THE PROPSHAFT OR AT HTE CRANK. i ALSO WANT TO KNOW HOW MUCH POWER IS LOST IN THE DRIVE AN AN ALPHA.
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CAN ANYONE TELL ME HOW MERCRUISER RATED THEIR UNITS IN 1984. WAS IT AT THE PROPSHAFT OR AT HTE CRANK. i ALSO WANT TO KNOW HOW MUCH POWER IS LOST IN THE DRIVE AN AN ALPHA.
The old "BIA", and now the "NMMA" has required a propshaft HP rating on all engine /drive packages sold since at least 1980, possibly earlier. A far as how much power it takes to turn an alpha... I don't know. Maybe 20hp?...
THANKS FOR THE INPUT MAN. WE'LLSEE HOW WELL THE ALPHA HOLDS MY 350 HORSE 350 SBC .I THIN KTI WILL BE OK BECAUSE IM ONLY MAKING 390 FT LBS OF TORQUE AND ITS MAKING IT A LITTLE FARTHER UP IN THE RPM RANGE BUT ILL FIND OUT.
I've heard that the Prop HP is 10% less than the Crankshaft HP...280HP at Prop=310HP so 30HP loss from Outdrive.
SShammy:
THANKS FOR THE INPUT MAN. WE'LLSEE HOW WELL THE ALPHA HOLDS MY 350 HORSE 350 SBC .I THIN KTI WILL BE OK BECAUSE IM ONLY MAKING 390 FT LBS OF TORQUE AND ITS MAKING IT A LITTLE FARTHER UP IN THE RPM RANGE BUT ILL FIND OUT. It should handle that. Just remember the biggest things that break drives are wide open takeoffs, and exit/re-entry under power. Go easy on the throttle, and change the gear oil often and you will be fine.
HEY I JUST GOT OFF THE PHONE WIH MERCRUISER AND THEYVE TOLD ME THAT THE RATINGS IN 1984 WERE AT THE FLYWHEEL. OH AND I WOULD VENTURE TO SAY THAT THEY WERE GENEROUS AT THAT. HE ALSO TOLD ME THt the alpha drive is good for between 300 and 310 propshaft hp.
:) :) :)