Absolutely not. If you are near sea level, the correct jets are already in the appropriate carb. If you re-jet richer, you will accomplish nothing but fouled plugs. Period. If you need to convert from the 4 to the 5 or to the 6, you replace the entire carb to get the correct CFM. Period.
Yes, Solas makes great props. The 4-blade models (both 5 and 7 pitch for the Tohatsu/Nissan 8/9.8) are super for sail applications.
do you want me to show you the page where johnson SPECIFICALLY says this is so Im not arguing...I agree....the bes way is to change carb completely however on some engines, specifically the one I mentioned
the johnosn 9.9 and 15 series its simply carb jet size and manifold...NOT CARB
Like others have posted before and have experience in this(I restore motocrcyles too) you can absolutely depending on where adjust your jet sizes for performance where you need it(most carbs come jetted for sea level naturally) if you are in a lake up in tahoe it makes sense to do your due dilligence and rejet...
the correct jets however are almost NEVER installed in your carb, especially if you live in countries like the good ole use or europe where epa and other nuissances DICATATE what power and emmissions you can get from a certain engine especially when its sold commercially to major areas.
so i disagree...but thats ok...to disagree....
this also comes from experience in small engine rebuilding...on water and off
for example most carbs especially on motorcycles these days have specific kits called smog block off kits, evap removal kits or in some cases even pilot jet cap removal kits as some carbs are soooooooo EPA compliant that they wont even let the owner fine tune the slow jet for easy starting depending on your altitude and climate
lets not even go there...its very easy to get a little more oopmh from these simple engines...especially once you have propped right
here is another tidbit
saying the jets that come with all outboards are perfect makes no sense...especally since many dinghy outboards for example used at idle when they were designed to run at wot or 3/4 foul plugs up naturally, especially if 2 stroke and hence why most older outboards had nice rich lean knobs to fine tune your idle mixture
if yo were a diligent owner you did this every time you started and stopped the engine
not here to argue just offer my point of view...and experience