The HP numbers are in
05-18-2010 | 08:42 PM
#1
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From: cedar springs mi
The HP numbers are in
Well this is what I ended up with not to bad. we will see how it works in the boat.Attachment 416608
05-19-2010 | 10:09 AM
#6
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From: Western Michigan
Congrats on the engines!
Also, I've been using the crank trigger system on my engines for the last several years now, once they're set the timing never moves!!! I will be using them on my next set of engines too
Also, I've been using the crank trigger system on my engines for the last several years now, once they're set the timing never moves!!! I will be using them on my next set of engines too
05-19-2010 | 09:31 PM
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From: NW Michigan
Looks great. I'm sure you have your mind made up where you plan to prop it however I would think you'd want to be a minimum of 700 RPM above peak torque. Regardless, job well done. What does Tom charge for dyno time?
05-19-2010 | 11:50 PM
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From: Tennessee
Nice numbers. It was good talking with you the other day.
I partially agree with both thought processes on proping it. Although you are only making a few more hp in the upper rpm, you still need to be close to 1000 rpm over peak torque with your max rpm. As getrdunn said, you want to have the peak rpm high enough so that you do not torque load the prop and force it to lift the stern of the boat. I would shoot for about5800-5900. That is enough above peak torque so as not to cause a handling problem, yet it is not to high to the point where the torque starts to nose dive. The few extra hp in the rpms above 6000 are not worth the loss in torque. I think you would start to lose speed if you propped it for over 6000 rpm because the torque drops pretty quick. The hp is not that good without the torque.
Anyway, excellent numbers. You should be happy. Good luck with it.
Eddie
I partially agree with both thought processes on proping it. Although you are only making a few more hp in the upper rpm, you still need to be close to 1000 rpm over peak torque with your max rpm. As getrdunn said, you want to have the peak rpm high enough so that you do not torque load the prop and force it to lift the stern of the boat. I would shoot for about5800-5900. That is enough above peak torque so as not to cause a handling problem, yet it is not to high to the point where the torque starts to nose dive. The few extra hp in the rpms above 6000 are not worth the loss in torque. I think you would start to lose speed if you propped it for over 6000 rpm because the torque drops pretty quick. The hp is not that good without the torque.
Anyway, excellent numbers. You should be happy. Good luck with it.
Eddie
