Motor height on transom.

[WASATCH CHARLIE]

Last year I mounted my V-4 110hp.Evinrude on its highest mounting hole...boat ran 42.4 mph on GPS but as soon as I tried to turn,regardless of trimming, cavitation...moved it down 1 hole,still ran 41.3 ..Trouble was,it blocked the transom drain hole. ... then last week,i ''spun'' the hub on my ''spare prop '' OMC 13X19. WOT/54-55OO rpm.
Put my old prop back on,lowered it one hole...now runs 38.9mph on GPS( from my truck) and 62.5 kmp (38.8) on my combo fish finder........so I know that's ''real '' speed. my old prop is also OMC 13X19 Alum.
prop is like new-no dings....I did put my old 4 stroke HONDA 7.5 on boat, 5gal.tank for main motor and 4 gal.for kicker... boat is a 1979 17FT.Double Eagle with canvas bimini top....
looking at a couple sites STATESIDE, guys are bragging 45-50+ mph. running older 90-115hp.OMC CROSSFLOWS on various hulls,INCLUDING deep vees...........on 16-18footers.
I run 2800-3000 rpm about 22-24mph . .. and am satisified with performance....besides,i can't afford to run WOT all day LOL
What are folks with similar rigs getting?
tight lines, Glenn

 

[casper5280]

My Yamaha 130hp 2 stroke on the same boat would do 45mph@5500rpm trimmed right out with 2 guys and a full load of fuel on flat water.

 

[profisher]

You have a choice..swing a bigger pitch prop and go faster but pound the wrists pins out of it or smaller pitch prop and get longevity out of it. I had a 17ft DE with a 115 Yamaha 2 stroke that did just over 40mph. I ran a 17 pitch stainless prop and because I often had 4 guys in the boat it showed piston drop (wrist pin wear) after 3 seasons. So even the 17 was too much prop. If I kept the boat I would have traded down to a 15 pitch.

 

[WASATCH CHARLIE]

Thanks for the replies gentlemen,. I know by lifting the motor,i can gain 1 or 2 mph,so I think i'll settle for what I have...it jumps right up on plane and then trimmed out,it runs fine.... over 20mph under 3000rpm works for me and if the ''lump on the chuk'' comes up,i get home a little quicker....
cheers glenn