whats too many rpms for x-flow

[havinfun]

hello everyone. trying to get the boat setup and want to know the maximum revs for a 1977 140hp evinrude. don't know whats done to the motor but runs real strong, boat is an openbow runabout. fairly heavy with dual batteries 20 gal gas and all the other usually junk in a ski boat. running a 13 x 18 laker prop has excellent hole shot. it will turn the prop 6800 rpms checked pistons tops after about 5mile wot run and all looks great motor has 150 psi all cyl. will this kinda revs hurt the old motor. i don't want to prop up because i use it for ski and tubing all the time. just want some experts advice.

another question does any one have pics of tuner and mid section drilling. i used the search feature and found lots of info just no great pics. just wondering cause it loads up idleing around getting skiiers.

again thanks to all how respond D.J. Walsh

[Michael Martin]

Your PRMs are a bit high. Really 5800 is where you want to be, if you want to motor to live more than a year. (IF its a stock motor)

Id grab another prop like a 20 or 22 raker to run & see if it makes a big differance in your hole shot. If it does then try a 4 blade.

Mike