markt111

My boat is a center console with T-Top running between 7000-8000lb depending on fuel, motors are 1994 Johnson 250 HP V8s counter rotating, no bracket,

I just added jackplates so I could raise the motors, they were very deep, prop center 9 1/2" below hull, cav plates were also below, raised motors2 1/2" can't go higher unless I run a low water pick up or add a nosecone which I may due over the winter

finally did some real prop testing this week, resulst below, all GPS speeds, light wind 2-3 ft chop

21* mirage plus

4000=40mph
5000=50mph
6100-6200=62.3mph

22* Mach stern Driver 4-blade

4000=41.5
5000=53.5
5800=61.7


day two one more 200 LBer in the boat, no chop

23* Mirage plus accelerator design

4000=43mph
5000=54.5mph
5800=62.0mph


I was expecting less speed out of the 4 blade Mach Stern Driver prop, haven't heard too much positive about them but it perfomed pretty well over all, only down fall was the boat was a little loose in the rear at speed with it trimmed up(scary!!!) I think this is just what any 4 balde will do to this hull due to the added stern lift, I think I need all the bow lift I can get with the weight and layout of the boat

all props had great hole shot, 4 blade obviously stayed on plane at lower speed which is not really a concern of mine, looking for best 4000rpm cruise and topend

also need to run a lot od positive trim to get the speed out of the boat 5/8-3/4 up on gauge, if I go higher it gets squirly!!

markt111

so to let you know why I post, want opinions on what wouls be the best prop for my setup, think I should see more speed out of it, here of other people running 70 with the same power, maybe they are not being honest????

do you think adding a nose cone and raising the motors more would be efficient in this case, I heard raising motors usually nets speed but can reduce bow lift which I need????????

mmwalters

I am have a buddys boat here, 1996 same as yours but with 225 johnsons best speed has been 58mph. Large stainless marine bracket with 22'' raker props. Your speed seems about right

RLW

I would post this thread over on the Prop Talk section.
Just do the old Copy/Paste and save yourself some typing.

In any case, seems right in line compared to some other CC boats in your weight and length.

throttleup

We have worked on a lot of these boats and with the power you have the speed is right in line of the other boats we have worked with.

Matt