SoCal Jet Boats
Tech Talk => Jet Pumps => Topic started by: eodjohnson on October 21, 2010, 07:58:07 PM
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i come from car world and torque gets me places but when i see the impeller charts they are all hp vs rpm vs impeller size
is torque not as important as hp in a jet pump?
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i come from car world and torque gets me places but when i see the impeller charts they are all hp vs rpm vs impeller size
is torque not as important as hp in a jet pump?
This could easily turn into a crazy long thread, so here is the first of many two cents... ;D
First I will be quoted as saying; "torque is king in a jet boat"...There, I said it. :sly:
A jet pump absorbs horsepower, but the "peak" horsepower need to be at a substantially lower rpm than in that of a prop boat.
So that being said, low end (low RPM torque) is absolutely useless, the pumps do very little work at a low RPM, so the torque required to get up to and passed about 3000 RPM is extremely low. The torque is required after that point though, and a lot of it, so I call it safe to say that your peak HP should occur at a low RPM and the torque curve should peak at the highest possible RPM and still make good HP..
Really, it is a balancing act between the two.
I think when most people think of a torque monster, they think of something like a stump pulling truck, there are more ways than one of making major twisting power.
I guess another way of stating would be; long stroke, big exhaust, hot ignition and decent compression....
GT
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ok good so it does have a say i feel better now.
from looking at all the charts i got the impression it wasnt usefull information
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ok good so it does have a say i feel better now.
from looking at all the charts i got the impression it wasnt usefull information
Where your projected motor make power how bigs the boat and what are you doing with it ?