99 40 hp johnson mods

[Kevodaniel]

Or we could put my tiller steer on that sst with that hydraulic jackplate

[Jonboat]

yeah that's what I was thinking... there sure isn't a lot of info on here about your motor wonder why?

[Powerabout]

there are 2 carb sizes for that engine, yes sst60 are the larger venturi but you will be on your own for the jetting.
The sst45 is a modified 45 ci engine that is the same as your basic design, it has the larger carbs, shaved head and a custom megaphone and adapter with reversed water flow.
All designed to suit the light tunnel boat it is used on.
Its a stock class but there are other mods for that engine, more comp would be ok and cut pistons skirt like the older 60hp

[OUTBOARDER]

Dose anybody have and info bout making a 40 a 50 or 55hp I know the carbs and reed cages are different I'm not sure about the head or exhaust I put 50 hp jets and boysen reeds in it and I'm not sure if the jets hurt or helped me it's on a 1648 weldbuilt with a 4in jackplate just got it put together only had it out one time so not much testing time thanks for any info

had a stock 96 50 johnson on a 16' Carolina Skiff Ran 43mph cosistently with a 21p omc alum prop.

[Kevodaniel]

had a stock 96 50 johnson on a 16' Carolina Skiff Ran 43mph cosistently with a 21p omc alum prop.

Was your motor a large or small gearcase the it have the small gearcase and the biggest prop I found was 11.75x19 it stainless if yours is a large gearcase can I run a large gearcase prop on a small gearcase lower unit

[OUTBOARDER]

Was your motor a large or small gearcase the it have the small gearcase and the biggest prop I found was 11.75x19 it stainless if yours is a large gearcase can I run a large gearcase prop on a small gearcase lower unit

aluminum 11.25 x 21p omc on 1996 stock johnson 20" 50hp , the 11.75 x 19 ran about 40mph

[OUTBOARDER]

Was your motor a large or small gearcase the it have the small gearcase and the biggest prop I found was 11.75x19 it stainless if yours is a large gearcase can I run a large gearcase prop on a small gearcase lower unit

http://www.boatracingfacts.com/forum...65-Clydes-Ride

different project with a 1985 40 converted

[Kevodaniel]

With the 12.75x15 I'm turning 5750 rpm so I think the 19p prop would be good if I I'm not satisfied I'll get it worked from my research they do not make a 21p prop for a small gearcase the biggest I found was a 19p

[thornl01]

You will be better off to go ahead & pull the powerhead & replace the tuner.

When you get this apart you will be amazed at how restrictive the internal tuna/muffler is.

get some 70/75 3cyl carbs, & 50/60 intake

you WILL have to rejet the carbs

[Kevodaniel]

You will be better off to go ahead & pull the powerhead & replace the tuner.

When you get this apart you will be amazed at how restrictive the internal tuna/muffler is.

get some 70/75 3cyl carbs, & 50/60 intake

you WILL have to rejet the carbs

I just got some 50 hp carbs and the part number on the intake is the same for the 40/50 for the preformance gain that the tuner will give it's not worth it to me to pull the power head right now maybe a later project bit thanks for the info