Gulfstream - Single Engine RPM/Speed question

[Gulfstream G]

I have a 2002 Gulfstream with a single Yamaha 225 engine. I'd like to hear from others with this set up as to their top speed /RPM and cruising speed RPM numbers.

 

[DB]

G...here are my #'s with a 15.5 x 17 SSII
RPM MPH GPH MPG
1500 6.9 1.9 3.61
2000 8.0 3.0 2.65
2500 8.7 4.6 1.9
3000 10.3 6.2 1.65
3500 13.1 8.0 1.63
4000 22.1 10.2 2.18
4500 29.2 12.5 2.33 optimum cruise
5000 34.1 14.7 2.30
5500 37.7 17.7 2.14
6000 42.4 21.4 1.98

 

[Gulfstream G]

Thanks DB. Are those numbers with a single Yamaha 225?