Enough pitch?

[Anonymous]

quote Richard A. White:

Wanting to chuckle as I know this will catch grief, BUT…..
Why in the world do you want to use an OMC and try to go fast?? Plant a Merc back there and let it ripo..
My 1947 Merc KE7, off a fresh rebuild, stock prop, does upwards of 22 mph, from a 10 hp, on my 14 foot 1963 StarCraft Seafarer.

I have the KE7 as 19.8 cubic inches, are you telling me it’s only making a half a horse per cube? Or is the 10hp designation one of Elmer’s marketing schemes? The follow-on KG7 was called "10+", the Mk15 16hp, and the Mk25 was called 18, all on the same displacement.

[dave-bernard]

same cubes buy different internals mainly reeds and carb.
KE7 4 reads
KG7 8 reeds

[vintin]

A friend of mine gets 25 mph out of an 1957 18hp omc pushing an AlumaCraft FD. I also know a lady who gets 24mph out of an 18hp OMC pushing a 1954 Alumacraft DR.

[RICHARD A. WHITE]

quote Phil B:

quote Richard A. White:

Wanting to chuckle as I know this will catch grief, BUT…..
Why in the world do you want to use an OMC and try to go fast?? Plant a Merc back there and let it ripo..
My 1947 Merc KE7, off a fresh rebuild, stock prop, does upwards of 22 mph, from a 10 hp, on my 14 foot 1963 StarCraft Seafarer.

I have the KE7 as 19.8 cubic inches, are you telling me it’s only making a half a horse per cube? Or is the 10hp designation one of Elmer’s marketing schemes? The follow-on KG7 was called “10+”, the Mk15 16hp, and the Mk25 was called 18, all on the same displacement.

The KE7 was from BEFORE Karl was forced to advertise "actual" hp at the same rpm as OMC was already doing…I do not remember but I think it was in the early 50’s he had to start telling actual hp at a given rpm. And remember I am "fat at 260+ lbs so a lighter fellah will do much better…

Can someone confirm?

http://www.richardsoutboardtools.com
classicomctools@gmail.com

[dave-bernard]

KE7 was late 40’s but had internal differences as I said before it was more like 14. his HP ratings were at omc rpm’s back then that is how they got away with it.
example a KG7 was 10HP at 4400 rpm but ran at 5600 rpm.

[billw]

I dunno…..It has been my personal experience that FDs and Fastwins can be pretty darn quick….I have owned and run both Mercs and OMCs…

That being said, as a kid, I had a Fastwin on an 8′ Minimax. I ran both a three blade aluminum prop and a two blade Columbian "speed prop." The latter was bought new with a lot of lawn mowing money and carried with it great expectations. It was a long time ago and i don’t remember the pitches or part numbers. However, I always felt, however unscientifically, (No GPS back then) that the three blade was actually a little FASTER…..

Long live American manufacturing!

[wiscoboater]

Scott, I have a few different props/pitches that fit the Mark 30. Since mine will not be going on a boat anytime soon…. You are welcome to try them all out and see if one works better for you. Let me know, Jeff

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