i have recently purchased CC (found on this site) and having gone through - tune, fluids , filters i am left with one question with tach reading, VDO- boat is 88 martinique 5.8 with what appears to be orig prop 13x13fed. tach shows no reading until revs are above 1000, on water when opened climbs to about 4200 when i adjust zero dial on back to about 5-600 at idle and then run it climbs to about 46-4700. i put old HAWK engine analyzer after removing dust and new 9v i presume it is fairly accurate as shows 550 at idle we then put some extension jumpers on and run while comparing dash tach with light load -300lbs wife and I (thats total not each)we still get 4500-4550 opened up ?isnt red line 4400
now looking for new prop as when loaded for wakeboarding- 1000lbs get some vibration through acceleration.
called Acme and they tell me that i could go down to 13x 10.5
i am more inclined to opt for #542 13x11.5 or 540 12pitch yet worried that may already be over revs? anyone using 542 or 540 that could shed some light as to how much more rev they see? and bigger question is why would i see over 4400 with what i presume to be factory orig?
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