Performance Improvements possible with newer 4 stroke outboards

[slowJEEP]

That Hobby, 750 and 850 sounds like a good time.

[Powerabout]

That Hobby, 750 and 850 sounds like a good time.

Racing any class with those engines always make a great class

[slowJEEP]

Merc 60 4S is just a smidge over 60ci though. 60.8 ish. Even though it's a turd in factory form, there are a few of us working to hop them up. Perhaps a 61 inch max would be better...

[Powerabout]

Merc 60 4S is just a smidge over 60ci though. 60.8 ish. Even though it's a turd in factory form, there are a few of us working to hop them up. Perhaps a 61 inch max would be better...

You can see why it went nowhere in the usa when a 45ci sst45 craps all over it

[slowJEEP]

Yep. Takes an expensive 4 stroke to out hp/ci a 2 stroke and the 60 merc is a far cry from high performance.

[Bateman]

I like mixing gas and hauling azz myself. I get tickled at my friends who think four strokes are more reliable.

[Flx]

Hi,

I am the guy with the boosted honda 50hp

Yes the camshaft made a hudge difference in the high rpm, i now keep getting the rev limiter at 6600rpm with 4 blade cleaver 10.5x18,

The engine is tweaked on the ignition by at least 3 degree of advance. This also make a hudge difference, let just say it is not a quiet honda anymore. Once you twist the gas, there just no lag, it will spin to the top.

Ive since bought a brand new boat, my next bet is a yamaha 70hp, these engine with a simple ecm reflash can gain 15hp, it would be even more with porting, camshaft and more compression.

The major problem i had with the honda is oil ingestion by the pcv tube at high rpm. It could be easy fixed with a catch can.

If you balance the engine i think it could run easy over 8k rpm. With headwork also !

Lundin marine can reflash any 4stroke and is located in norway. He is a king pin.
JBmecanical is located in australia. That guy live tune outboard.