Yamaha HPDI - 150 vs 300hp

[bennettrp]

Hi,
I've got the 150hpdi. When I look at specs, there doesn't seem to be any diff btw the 150 and 200. If I recall correctly displacement and comp ratio are the same. Which makes me wonder if the diff is in the tuning.
Does anybody know?
thx
Dickd

 

[JB]

Re: Yamaha HPDI - 150 vs 300hp

Yamaha knows, and they aren't telling.

 

[Silvertip]

Re: Yamaha HPDI - 150 vs 300hp

This question gets asked alot and the answer is always the same. If you look at specs for engines from every manufacturer there are typically several with varying HP with the same displacement. Yes -- its in the tuning, injection or carbs, porting (two strokes). camshafts (four strokes), head design (four stroke) and exhaust and intake tuning. These changes are easy for the manufacturer to do but converting a lower HP engine to the equivalent of higher HP version is generally not worth it from an economic standpoint.

 

[bennettrp]

Re: Yamaha HPDI - 150 vs 300hp

This question gets asked alot and the answer is always the same. If you look at specs for engines from every manufacturer there are typically several with varying HP with the same displacement. Yes -- its in the tuning, injection or carbs, porting (two strokes). camshafts (four strokes), head design (four stroke) and exhaust and intake tuning. These changes are easy for the manufacturer to do but converting a lower HP engine to the equivalent of higher HP version is generally not worth it from an economic standpoint.

Thanks. guess I was hoping that the answer would be as simple as "restrictions" and PCM tuning. But then again, I guess everybody would be into tuning if it was that simple.:/

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