400 HP Inline 4 Billet Engine? I think so...

Droste14

Be About It!
Location
Wichita, KS
kawasaki-jet-ski-ultra-300x-7.jpg
 

DAG

Yes, my balls tickled from that landing
Location
Charlotte, NC
Thats not a 4 stroke its a duel 2 stroke.. The 1st and 3rd cylinder hit at the same time.

...ikidd
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
I am going to go ahead and tell you why that won't work in a ski, crankshaft torsioning is your problem, there is a reason why there are no inline fours, a triple has severe crankshaft torsioning as it is, another cylinder only complicates the issue further. Crankshaft torsioning is the twisting of the crankshaft over the length span, it is enough of a problem that Yamaha engines have lower compression and less timing on the rear cylinder to compensate for the crankshaft torsioning., You might be able to get by with this in a standup, it would never work in a sitdown watercraft period.
 

DAG

Yes, my balls tickled from that landing
Location
Charlotte, NC
Why would a crouch not have the same crank torsioning as a standup? If anything I would think it would be worst in a standup they way we turn everything for the big "hit".
 
Location
hhh
Why would a crouch not have the same crank torsioning as a standup? If anything I would think it would be worst in a standup they way we turn everything for the big "hit".

shear weight

who cares about a couch here anyway, at least not trying to hot rod one
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
Its called pump loading, standups do not and are not capable of loading the pump the way a couch or jet boat does. On a sled you have no direct connection from the engine to the track, its belt drive with a clutch setup, the belt does not load the enging the way a direct drive pump does.
Now I suppose if you ran a firewall mounted tank and battery and ditched the waterbox you might get that in a standup, one question though,where are the exhaust pipes going to go?

Go ahead and argue with me though, I have never worked on anything, I don't have twenty plus years in the business and I have no idea what I am talking about.
 
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