All that extra fuel must be going somewhere. The fuel curve must be fatter than a hooker on a salary...

Hi!

There is a test when the engine consume 56 liters at 3,700 rpms. My 450R consumes almost the same. 48-50 liters at 3,500 rpms and approx 60 liters at 4,000 rpms.

So hopefully its a hope

Cheers Toffen

The 500 HAS to have bigger injectors compared to the 450. It's not just the software programing that makes the 50 more HP.

If the injectors are bigger, you shorten the opening time to get the same fuel flow.

Again, we are not curious about why a 500 hp engine uses more fuel than a 450 hp engine when it puts out 500 hp.

We are curious about why a 500 hp engine uses more fuel than a 450 hp engine when both put out 250 hp.

Yeah, I saw that test, too, but the posts here indicate something else.

On the other hand, even at Norwegian fuel prices, you are a lucky man if fuel spend is a meaningful part of your total boating spend...

Hi!

When I swopped from 350 Sci to 400R, midrange fuel flow was the same.

I have asked the national distributor to provide some fuel data.

Cheers Toffen

With modern fuel management technology, there needs to be a really good reason why midrange fuel flow for 450R to 500R wouldn't be the same as well.

That's what makes this thread so interesting.

Hi!

New test https://www.yachtingnews.com/technohull-38-grand-sport/ with twin 500R.

3000 rpm = 64,1 liter / 2 = 32 liter per engine
3500 rpm = 82,1 liter / 2 = 41,1 liter per engine
4000 rpm = 121,4 liter / 2 = 60,7 liter per engine
4500 rpm = 152, 8 liter / 2 = 76,4 liter per engine
5000 rpm = 201 liter / 2 = 100,5 liter per engine

My 450R:

3000 rpm = 40 liter
3500 rpm = 48 liter
4000 rpm = 59 liter
4500 rpm = 72 liter
5000 rpm = 85 liter

So here we have a different figures here..

Cheers Toffen

You need to understand the load on the engines at those different RPMs for the comparison to be meaningful.

Hi,

I see the point, but the Technohull 38 grand sport is 3,500 kilo dry weight. Phantom 25 is approx 1,200 kilo.

Cheers Toffen