Performance numbers for older 265 Grady

[chopchop]

I'm getting no where near these numbers. I'm getting 1, maybe 1.1, I was hoping for 1.3. 1.6 seems very high though. Any other Real World vs Grady Performance numbers?



GRADY-WHITE BOATS' PERFORMANCE TEST

265 EXPRESS

Test Date: 6/14/1999

Engine : T250 EFI YAMAHA

Prop Size: 15 1/4 x 19 ssm

Accessory weight including fuel, persons, gear : 1330 LBS.

Hardtop: YES

Bow Pulpit: Yes Yes


TESTED TESTED TESTED TESTED
R.P.M. M.P.H. G.P.H. M.P.G.

1000 6 4 1.5
1500 8 6.1 1.3
2000 9 10.1 0.9
OPTIMUM 2500 12 14 0.9
3000 25 16.7 1.5
CONDITIONS 3500 30 19 1.6
4000 36 23.8 1.5
4500 41 31.8 1.3
5000 46 43 1.1
5500 51 56.3 1


Optimum cruise: 30 mph @ 3500 rpm

Top recommended R.P.M. : 4500 ~ 5500

** This report should be used only as a general reference guide.**

The following is a list of variables that can affect performance :

Wind Engine Trim
Current Bottom Paint
Sea conditions Trim Tabs
Speed Curtains
Engine Performance Tops
Transducer Gear Placement
Trolling Time Prop Size / Condition / Type

 

[Tuna Man]

I've owned or have had family members own a total of seven Grady Whites. Every one of them would closely match the factory test, maybe lose a mile an hour or two. Every one of them was bottom painted but were very smooth. Remember, most boats are not loaded with options and electronics during testing. On your boat I suspect you may have as much as five hundred pounds of gear, tackle, options, electronics and bottom paint. IF your bottom paint is very smooth, I would think your engines are at fault.

I'm guessing your boat is loaded with the above items and your boat bottom is anything but smooth. Just for reference on a 1989 28 foot Grady Marlin the boat topped out at roughly 34mph with a fouled bottom. After it was sanded smooth and repainted the boat topped out at 44mph. Not only did top end suffer, I'm sure fuel economy suffered but the boat had not flowscan to confirm my suspicions.

Hope this helps.

 

[onoahimahi]

Your numbers sound too low. Do you have 17" or 19" props? What is your wide-open throttle RPM? You didn't list units - are you citing MPG or NMPG? Did you optimize trim? Are you motors mounted too low?

There is a recent discussion here for Sailfish. I'd ignore numbers for cases where the boat may be overpropped:

viewtopic.php?f=2&t=22108

 

[chopchop]

I have 19 props, WOT goes 5100 on medium load and 1 person. Just a little trim tab and different tilt configurations with the motors. that why it seems to change from 1 to 1.1.

You think the prop needs to be reconfigured?

 

[onoahimahi]

I have 19 props, WOT goes 5100 on medium load and 1 person. Just a little trim tab and different tilt configurations with the motors. that why it seems to change from 1 to 1.1.

You think the prop needs to be reconfigured?

I noted that the 19" propped Sailfish were getting 20% better fuel economy than the 17" in that thread so I was wondering which camp you were in.

There is a 265 review here which gives numbers from 1 to 1.25 which also seem low to me (because I am assuming it should do as well as a Sailfish.)
http://www.sportfishingmag.com/boats/bo ... 65-express

Perhaps some 265 owners will chime in.

My buddies 1998 Marlin cruses between 1.0 and 1.1 MPG all day long with the original twin 250's.

(Note that 1 Nautical MPG is equal to 1.15 Statute MPG so make sure your device is set to Statute miles for this)

 

[Sea Shift]

Kind of a silly question, but are you getting the 1 -1.1 from topping off the tank or the Yama fuel manager? If the latter I would do a real world test to be a little more accurate. I am in the 1.3-1.5 on good tuna runs.

 

[chopchop]

What props are you running?