R-29 and R-31 Engine Change to D4 320

[FWTMD]

I see that new builds on the R-29 and R-31 will be with the Volvo D4 320, instead of D4 300.

I am not experienced in using performance tables of the sort Volvo provides, so I'm asking what performance differences should be expected.

https://www.volvopenta.com/marinecommer ... 4-320.html

If you click through that link into specifications you can download a PDF on performance comparisons charts.

It appears the 320 adds 100 RPM at the top, and some very slight improvements in fuel efficiency in some RPM ranges.

What is the reason for the change, and what might be expected in performance differences?

Thanks in advance.

 

[iggy]

I think this does into your question better than the other link https://www.volvopenta.com/marineleisur ... -big-.html

I read in a Mag somewhere, about 5% better HP and fuel consumption.

 

[FWTMD]

Thanks

I guess what I'm getting at, is with higher RPM at WOT, the fast-cruise sweet spot (whether using 80% or 85% of WOT) seems like it would be just under 100 RPM higher. Fuel consumption at a given RPM is pretty identical up to that sweet spot then the 320 has a slight edge. But at that sweet spot there is still more fuel consumption for the 320@sweet vs the 300 @sweet.

The higher RPM at WOT would appear to give more speed there, but that ignores hull design impacts.

There is a more significant difference in torque, but I frankly don't know what that means in terms of on-the-water performance differences.

Your article mentions longer maintenance cycles which is always a plus. But it would be great to understand just what that means. Annual is annual. Annual + 10% doesn't deliver anything that's practical other than not pushing any cycles to limits.

 

[Kevin Lamont]

Hey there,

With the changes Volvo made were more of the electronic changes. They changed the EVC system to a new platform, the main power/GND posts are no longer on the starter and now on a buss bar style. They also made it easier for manufactures for twin or more engines to be connected together. The performance is kinda more less a cherry on top, I have to say from personal experience running the new engines it seems to be smoother and a bit quieter. Mainly Volvo improved on areas they wanted to make better, slimmer and easier access. Hope this answers any questions you may have.

Thank you,
Kevin Lamont

 

[FWTMD]

Thanks Kevin.

Smoother is nice. Quieter is nice. Better performance is nice. A bit more at the top end is always appreciated when its needed.

Why did you elect to move up to the 320 when the 300 was similarly upgraded?

 

[bill46]

Can the D4-300 be updated to 320?

 

[Kevin Lamont]

Thanks Kevin.

Smoother is nice. Quieter is nice. Better performance is nice. A bit more at the top end is always appreciated when its needed.

Why did you elect to move up to the 320 when the 300 was similarly upgraded?

Your welcome, Volvo has discontinued the D4-300 and the D4-260 so now we use the D4-320 and D4-270. Also I forgot to mention that one of the biggest upgrades was a engine mounted sea strainer which is VERY easy to service now with a sight on the top so you dont have to try and see from the side.

Thanks,
Kevin Lamont

 

[Kevin Lamont]

Can the D4-300 be updated to 320?

Hi,

Technically yes however, you would need to buy a whole new engine, the appropriate harnesses and new throttles as it has all changed and cannot be used on the new generation of engines.

Thanks,
Kevin Lamont

 

[FWTMD]

Thanks Kevin. That was not at all clear from the Volvo pieces I found.

And good news on the easier maintenance.

All in all, good news from end to end.

 

[Cessna172]

Can the D4-300 be updated to 320?

Hi,

Technically yes however, you would need to buy a whole new engine, the appropriate harnesses and new throttles as it has all changed and cannot be used on the new generation of engines.

Thanks,
Kevin Lamont

Hmmm, now that seems like an equitable solution : ) Now just dipping my toes in the water here...
...what does a new D4-320 go for these days?