Year of the power rating switch

[scrubs]

"Does anyone know what year ma

"Does anyone know what year manufacturers switched their power rating from the power head to the prop?
Just wondering because i have a 1958, 18hp that is giving me fits (see 18 hp backfires when cold), and i`m thinking about buying a newer motor. I`m being told if i get newer 15hp i won`t loose any speed, because the ratings are different. Is thiis true?

Thanks in advance for any info"

 

[jwbmarine]

"they used to rate them,at pwr

"they used to rate them,at pwr hd,..then,in the mid/late 80's,they rated them at the prop."

 

[vics]

"The power rating was switched

"The power rating was switched from power head to prop following the adoption of the ICOMIA standard 28-83

see http://continuouswave.com/whaler/reference/ICOMIA28-83.html

Certainly all quoted at the prop by 1984 ... I still have the 1984 brochure"

 

[scrubs]

"Thanks guys, that`s a handy p

"Thanks guys, that`s a handy piece of info while shopping.

How much hp does a motor my size (18 hp) lose going thru the lower unit?"