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post #4 of Old 10-14-2010
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I have 3gm with the maxprop. I can hit around 3400-3600. I just talked to Larry Berlin at Mac Boring and he said you should run at max a few hours each month to burn off the varnish. he also said the tachs are notoriously inaccurate and you should have a handheld to calibrate at different rpms.

I usually run mine around 2700 as that provides me with the best speed/efficiency ratio. For me that's a little over 5 kits and burning a little over a half gallon/hr. But I'm always loaded down into the water line stripe. If I take it up to 3200, it's a lot louder and burns a lot more fuel for marginally faster speed. I do run it high once a while as recommended.

Forgot to add, your dealer is wrong. The maximum rpm is for the engine - not a prop/engine combination.

PSC 31 #84

Last edited by stevemac00; 10-14-2010 at 06:39 AM.
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