Tech question - Yanmar 4LHAs

[backwaters]

Hello all,

I'm asking this more out of curiosity than anything else:

Yanmar 4LHA-DTZP = 200 hp
Yanmar 4LHA-STZP = 240 hp

The engine specs look identical: both 3.445 litre displacement, both turbo intercooled.

So how does Yanmar squeeze an extra 40 hp from what appears to be the same engine? Does anyone know the difference (mechanically) betweeen the two? I can't seem to find a website that lists all the suffix codes!? I know Z is for sterndrive.

Regards, -Jason

 

[Danfarry]

Jason

have a look here: http://www.yanmarmarine.com/theme/y...al/4LHA-HTP-DTP-STP-Z/4LHA-HTP-DTP-STP-EN.pdf

I think they use an aftercooler for the higher power versions