repower 33 f-250's

[tony-sally]

just repowered my 33 with f-250
need some performance stats
I run my boat- full fuel & water
bottom paint full curtains
outriggers and open arty anttens.
what are you people getting for
a cruise speed mph or knots
gph and rpm's.I est the weight
of my boat- ready for offshore
fishing trip to weight 14500-
15000.also what are you getting
for max rpm's? grady says between
5000-6000 to big a spread for
me I 'am looking for more like
5800-6000 what do you think
thanks in advance TONY

 

[Tuna Man]

Tony.
Not sure what you are asking. If you are asking what prop pitch should be I would thin 17" or so. On my marlin with the same 250's as your new ones, we hit 5900 loaded with 19" props.

Let me know if this is what you are asking.

 

[Kevcros]

I just checked my stats this weekend in FAC conditions-- 5600 RPM doing 31 knots at a 1.0/ mpg---

 

[tony-sally]

33 repower

I just checked my stats this weekend in FAC conditions-- 5600 RPM doing 31 knots at a 1.0/ mpg---

Thanks Kevcros
is your boat some what set up like
mine with weight? also are you
useing 87-or-89 octane I know
some marinas only have 89 octane
or 87 & 93 octane like mine.also
I take it that 5600 rpm is your
max rpm.Also what is your
cruise rpm & speed and at
what gph
thanks again Kevcros, TONY

 

[Kevcros]

5600 was pinned-- It was turning 30.9 knots at a shade over 1.0/ mpg--

My cruise is really 4800-5200 turning 26-28 knots at ~1.1/ mpg

Same rigged boat--outriggers, bottom paint, fuel, water, 4 people, 200# ice, full gear, etc.

 

[Kevcros]

Sorry-- This was with 89 octane gas.

 

[Stonewall]

Cruise at 48-4900 RPM and about 29 MPH. At that rate I'm burning about 28 GPH. Full out at 58-5900 RPM I can get 40 MPH.

Numbers are with 89 octane, full water, a ton of gear (my wife stocks the boat with everything you could possibly need!) most time 1/2 tanks of fuel and the engines trimmed up

On most trips I'm averaging 1.1 - 1.3 MPG.

 

[Kevcros]

Interesting that your top end is higher than mine-- Could be conditions, weight but i am not seeing over 31 knots at 5600 rpms--Also, your mpg seems a bit better--How mucha re your engines trimmed ?

 

[tony-sally]

Cruise at 48-4900 RPM and about 29 MPH. At that rate I'm burning about 28 GPH. Full out at 58-5900 RPM I can get 40 MPH.

Numbers are with 89 octane, full water, a ton of gear (my wife stocks the boat with everything you could possibly need!) most time 1/2 tanks of fuel and the engines trimmed up

On most trips I'm averaging 1.1 - 1.3 MPG.

stonewall their pretty good stats but you said your
running 1/2 tanks fuel a full load is app. 2200lbs
that's telling me your 1100 lbs lighter than
kovcors. TONY

 

[Stonewall]

I usually run on the Chesapeake Bay. I am never more than 30 minutes from a marina with gas, so it just doesn't make sense to carry around all that extra fuel. I have no problem hitting 40 MPH at full throttle. Went from Annapolis to Indian River Del and back (round trip was 235 miles) and averaged 1.15 MPG.

 

[Bob's Cay]

Cannot remember the conversion factor, but it appears you are comparing miles per hour to knots per hour. Convert it and I bet your speeds are close.

 

[tony-sally]

5600 was pinned-- It was turning 30.9 knots at a shade over 1.0/ mpg--

My cruise is really 4800-5200 turning 26-28 knots at ~1.1/ mpg

Same rigged boat--outriggers, bottom paint, fuel, water, 4 people, 200# ice, full gear, etc.

Kevcros, I'am shure your running
the same prop as I am 15 1/2+ 17
Stonewall is turning close to factory
spec. but like I said I est the weight
of my boat- @ 14500 + lbs
and stonewall is running 1/2 fuel
would be 1000 lbs less would
put him just around the test
weight for grady. Do you know
of anyone that has tried diff.
props to get the rpms up
for the heavy loaded boats
thanks in advance. TONY

 

[Kevcros]

I spoke to Grady about changing out my prop (i wanted less top end and better fuel consumption)-- The canned reply was that the 15 1/2 was the best all around prop-- A change out would impact performance/ handling--- I think you may be right on the weight-- i am running a LOADED boat with tons of gear, at least 200# of ice, full gas and 4 adult guys-- I will retest tomorrow but 30.9 knots at 5600 is my pinned speed (although engines trimmed full down)--

 

[tony-sally]

repower 33 f 250

well looking for a few other 33
express owners with their cruise
speed,gph,rpm.also max rpm
and also how boat- is loaded
trying to determine weather
I'am going to look for someone
who can do some prop work
so boat- can achive 5800-6000
rpm still with good stats
thanks in advance.     TONY

 

[tony-sally]

Re: repower 33 f 250

well looking for a few other 33
express owners with their cruise
speed,gph,rpm.also max rpm
and also how boat- is loaded
trying to determine weather
I'am going to look for someone
who can do some prop work
so boat- can achive 5800-6000
rpm still with good stats
thanks in advance.     TONY

what is the cruise rpm most of
33 express owners use and has
anyone changed props?
TONY

 

[capeboter]

Tony,

I ran from east end of Cape Cod canal to Provincetown this past weekend at just about 1/2 full ( maybe a little less) and ran at 5600 with about 30 degree of tabs ( I kept playing with the tabs) and the engines trimmed almost 1/2 up. I had 10 people aboard and we hit 40 mph (sorry didn't check knots) and burned about 39 gph or almost 1gal/mile, also had flat calm conditions and very slight wind.
On the way back across Cape Cod Bay I had a full fuel load with the same amount of people and the same weather conditions. I ran WOT at 5600 and had basically the same performance. I lost 2 mph with the extra fuel weight.
By the way distance at that speed was approximately 25 miles.

After all that though I usually cruise at 46-4800 with about 26 gph consumption and a mph of 26 -28.

Mike

 

[tony-sally]

repower 33

Thanks. Mike
for the info my new engines
are not broken in yet.You said
your engines were trimmed
1/2 up do you recall how many
bars this was on your yamaha
gauges? also i'am shure your
engines are mounted all the
way down this is the way grady
sets them up do you get any
cavitation when turning port &
startboard on hard turn? I'am
also looking at height of engine
for better performance.
thanks in advance. Tony

 

[capeboter]

Tony I do get some cavitation when the engines are trimmed up with the power tilt. Mostly if I slow down. If I dont trim the engines down then they cavitate. Sometimes I'll get it while turning. As far as how many bars on the guages, I'd say four (4) bars. I will stop tilting/trimming them when the fourth bar comes on. I'm not near the boat till the weekend so I'm not sure of the engine height.

 

[valtech]

33 Props Engines Speed

I just put a fresh set of 15 1/4 X 17 yahmaha saltwater II props on my 2003 Grady with 225's. Fresh paint and full load of gas, made it 38mph. I cruise at 4800-4900 RPM at 30mph. Trim just under 3 bars, trim tabs full up.

To find your optimum effeciency watch your rpm gauges. Trim up until you start hearing some cavitation or see your rmp's jumping, then back it down a bit until its steady. Use your trim tabs to keep the boat level but bow full up is where I get my best efficiency/speed.

Clean bottom is a huge deal! My bottom didnt look too bad and had very little growth after the winter, but my hull performance went to crap. I couldnt get over 28 mph with the mild growth. I guess there is a lot of surface area under there and if you think about it and add all that mild growth up over that full area it really adds up. Might as well throw a few 5gal buckets on ropes behind the boat.... Like your momma always said "Clean your bottom! ".

Also I had a small distortion in one of my props and when I changed them out to the new ones, I went from tops 30mph to 38mph at WOT (5400-5600 rpm).

Well thats my two cents, hope this helps.