17'glass cuddie cab 90hp vers 115hp

[trex]

Any body have a 17'glass cuddy cab with a 90hp optimax what ltrs per hour average

[craigie]

G'day Trex,

Your question is a touch on the vague side, so I hope I'm giving the answer your looking for.

I run a 115 Opti on my 17 foot Runabout and can give the fuel figures for this setup (should be similar to your rig).

Planning speed (17 kns) is at 3100 revs for a fuel burn of 12 litres per hr

On 3500 revs, speed is approx 20kns for a fuel burn of 14 litre per hr
on 4000 revs speed is approx 24 kns for a fuel burn of 17.5 litres per hr

Flat out at 5800 revs, speed is 40 kns for a fuel burn of 37 litres per hr

At Idle speed 650 revs, speed is about 2 kns for a fuel burn of .6 of a litre per hr.

Cheers
Craigie.

[trex]

Thanks very much Craige that give me a prity good idea of what to expect I'm swapping my 115 2 stroke merc for a 90 opi.
and wasn't sure if I was making a mistake

Laurie

[craigie]

Laurie,

Forget the 90 opti, just go for a 115 opti, they are the same weight, so think of your power to weight ratio.. You will loose a bit of performance dropping back to the 90 hp from a 115 hp.

Would be interested to hear your fuel consumption figures at some stage. You may have to run a 90hp a little harder to maintain cruise speeds which would therefore effect economy ???

Cheers
Craigie.