Yanmar 315 or volvo D6 330 hp?

[peterwhite]

Just been out in a new arctic 37 with twin yanmar 8lv 370's and zt370 legs. Extremely impressive pickup and so smooth right through the revs. Impressive fuel economy too. Only thing to note I'd use the bravo three props and not standard issue yanmars. Bravos huge improvement in performance which was good too. Cruise 3k rpm at 41 knots and flat out at 55. Good for a big lump of a boat.

[willk]

Can you elaborate on the improved performance of the Bravos please?

Acceleration, Top end, Grip?

[peterwhite]

A general improvement in all areas. Around three kts on top end with a noticeable improvement on grip especially on pick up when the turbos spool up.

[willk]

Originally Posted by peterwhite

A general improvement in all areas. Around three kts on top end with a noticeable improvement on grip especially on pick up when the turbos spool up.

Interesting - thanks. I had a brief chat with the skipper of an 11m Redbay that was fitted with a pair 320hp 8-LVs. He was of the opinion that they outperformed the Yamaha 315s that he used in a similar vessel - mainly in the pick up - she was much faster out of the hole with no loss of fuel efficiency.

Twin turbos on a V8 - what's not to like

[peterwhite]

Too right!!! I put pics up under the nice rib thread.

[boofy]

Originally Posted by willk

Hi Boofy,

The ZT350 clutch wasn't up to the job. I don't think it had anything to do with heating/cooling, more that it couldn't handle the torque. The water for the combo was all introduced from the leg, IIRC. Yanmar issued a FOC replacement clutch mechanism for existing ZT350s and further beefed this arrangement up for the ZT370s as they have to cope with the huge torque from the new V8.

I did get a drive in the 315/370 combo. It was a very smooth change and ran well, although I think that the leg gearing didn't suit the boat in question at that time - since swapped out I believe.

Thanks to both reply's, much appreciated.

[Cookee]

I heard all the same things about the ZT drives and how they have been uprated, shame they're not built for over 55mph. The 315 is old school technology and the 8-LV (320 or 270) is a much better engine, it's a V8 with all of the latest injection technology and based on the new Landcruiser engine (just like the 315 was based on the old LandCruiser engine) - if it's in the budget I would choose the 8-LV every day over the older 315 and all of the competition!