need advice for a 1999 18'4 proline stalker

[hookerup]

Hi all,
 I am currently in the rebuild of a stalker flats boat and was wondering if anybody has any input on some things.
First i am repowering the vessel, it had a 135 merc two stroke carb engine on her, top speed was at  40 running light. I would like to cruise around 40 -45 and was wondering if a 150 would do the trick or do i need bigger?
 Next, has anybody ever ran a jack plate on one? is there a noticeable difference? or not worth the expense?  Thanks!

[231CALIFORNIA]

dont know about the jackplate myself but a few more hp, the right prop and proper trim and you should be moveing at least mid 40s(mph) with a 150.
some engines are rated optimistically and some are under rated.
there used to be a big  variance in performance between different 150s.
if your 135 was topping out below 40mph lightly loaded it might have been
set too deep, trimmed bow down,propped a bit off, was it reaching
WOT RPM rating.?
Anyway a modern 150 would be expected to do better ,especially if propped for top speed instead of hole shot.
3blade stainless(thin blades), propped to lower end or middle of wot range.
But in real world many of us are better off with inexpensive aluminum props
set up to give WOT Max rpm loaded if thats how we fish.
that would give you top of rpm range WOT lightly loaded.
also if you are speaking in knots 40 mph is about 35-36knots /NMPH
also. this is a very fast CRUISE SPEED for extended periods.
if you want to cruise  long distances over 35knots 
IMO you want max hp your transom can safely hold.
what does your uscg plate say for HP?
check your speed with a gps or paddle wheel sensor not a pitot tube speedo.

[hookerup]

Yes, Gps read was 42 mph , running 5600 slightly trimed with a four blade stainless prop ....with bottom paint. The vessel no longer has bottom paint and has 4 coats of highly tefloned wax, sooo i am guessing maybe 46. I Fish 3-4 times a week and sometimes travel long distances so i just want something to get from a-b a little quicker and better on fuel.
.But a 99 135 merc does not know what fuel economy is....so it will get replaced with a 150 opti xs i am thinking. And these boats do not trim like most, even if you trim the motor up , you can get the bow up about 5 inches. But even soo... she rides amazingly well, def one of the better riding flats boats.
I am personaly a Yami guy....but i have heard nothing about good things about the merc and they are like 2k cheaper than thier counterparts.
Oh, and if anyone is looking for a console for one of those boats....i have the old one REAL cheap.

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