"Honda" porting

[stefan]

Hei i follow some of the all motor honda drag racing scene and some the engine make 500+ hp on 2,7 L engines, this is natural aspraited so no turbo NOS etc. This with realy high RPMes but seeing the porting on the cylinder heads they have what they call dimble porting, have this been tryede on freestyle jetskies or is this not ideal for jetski freestyle application ???

 

[yamanube]

I dimpled my intake like that and made nearly 500hp, kept stripping driveshafts so I ended up polishing it like everyone says to do, now I know why.

 

[Big Kahuna]

I would say similar to having the intake track rough so the fuel charge does not stick and stays mixed up. Keeps the atomization mixed.

 

[Harbor]

Our pwc intake tracts are so complicated, be nice if it was a clean, tube and bowl shape like a 4 stoke eng.

That dimpling increases the surface area.