Gulfstream Power / Performance

generalee · Jun 29, 2008

I have been shopping for a good used Grady White Gulfstream. On Saturday I had the opportunity to take a trial ride in 2002 Gulfstream powered by a 225 hp Yamaha 4 stroke. I was surprised by the high rpm required to produce speed for this hull. The following performance numbers are from my notes taken at various times during the trial:
4900 RPM - 22 mph
5000 RPM - 24 mph
4600 RPM - 22 mph - after some engine trim
6000 RPM - 31 mph WOT - some engine trim
No fuel flow gauge to record consumption rate. Based on how hard the engine was working, no doubt fuel consumption was high.
Several factors influencing the performance ( or lack of same ): The boat stays in the water, has bottom paint, some fouling noted on bracket and lower unit where water contacts it when tilted. Main fuel tank empty (found that out the hard way), Aux fuel tank 1/2 full. 2 adults on board. Hard top. Very little gear on board.
Looking at advertisements in this forum and other sources I read of much better performance from the F225 Yamaha. And even better from 250hp. The numbers are all over the place. In talking with owners having Gulfstreams for sale, they report better performance.
I will appreciate any feedback relative to what REAL performance I should expect from 4 stroke 225hp, 4 stroke 250hp and the same power options in 2 stroke, and for twin engine configurations. No doubt there are many reading this forum with first hand experience in powering a Gulfstream. I would like to have information not influenced or perceived by me as possibly being influenced by the desire to sell a boat.

Also, any leads on Gulfstreams for sale not posted on this forum will be appreciated.

Thanks,

wlewis · Jun 29, 2008

My Gulfstream with an ETec 250 cruises at about 24kts (27.5 mph) at 4500 rpm. Top end, around 5700 rpm is around 35 kts (41 mph). I have bottom paint. My old 225 Evinrude was about 2kts slower.

ocnslr · Jun 29, 2008

I have found that even a little fouling, such as barnacles on the last two inches of the trim tabs, can significantly degrade performance.

The fouling you note on the bracket and lower unit would be more detrimental. And the bottom could be in bad shape as well.

If you are interested in the boat, then insist that the owner haul it, clean it, and then try for another sea trial.

You don't indicate what prop is on the boat, so can not do a prop slip calculation for you. Slippage goes up considerably when the bottom is fouled and the boat just won't move.

Brian

catch22 · Jun 30, 2008

The Gulfstream is a pretty heavy boat with a wide beam. It does take some serious rpms to keep it on plane, (at least with a single). Imo, 225 is marginal for that boat, especially since it's a Yamy 4 stroke. Don't get me wrong, they make an excellent motor, but from what I've heard, their 4 strokes are not putting out their rated hp. Even if that's untrue, they have a reputation of lacking any real get up and go, compared to a 2 stroke. You load that boat up with passengers, gear, fuel, etc and I think you'll be over loading an already over worked outboard.
I had a 91 Gulfstream, with a 2000 250 OX66, (2 stroke) I was happy with it's performance, but I wouldn't want any less hp. I used to cruise about 4300-4500, 24 to 28 mph, depending on load. 4700-4900 would get me over 30 mph, and 5500-5600, (wide open) and I'd almost see 40 mph... again, light load. I think around 4100-4200 was the minimum to keep it on plane.
If it were me, I'd keep looking. Twin Yamy F150's or twin 200 HPDI's. Might be tough to find, but even a pair of e-techs. At the very least a Yamy F250, and I'd have to give it a serious shake down.

generalee · Jun 30, 2008

Thanks for the information.
The condition of the bottom may have been a bigger influence than I realized. I was told the bottom had been cleaned and painted recently. "Recently" was never specifically defined. I will appreciate receiving other opinions, experience and thoughts on powering a Gulfstream.

BobP · Jun 30, 2008

Grady equipped that boat with an F225 because the F250 was not out yet as I recall. And all those prior years it got the 250 2 stroke, a higher torque engine. Grady also offered twin F200s and nixed the aux fuel tank option for twins to compensate for added 4 stroke V6 dead weight. The F150s were not out yet.

Grady and others even Parker did the same thing and attempted to make up for it via prop pitch.

Grady proped the boat to satsify climbing out of the hole instead of lingering in the hole, Parker did the opposite - pushed for higher speed so the WOT RPMs is barely cutting Yamaha spec.

In either case, customers are going to complain.

I your case of interest with this year model, if you don't load the boat to capacity with people / gear, could care less about time to accelerate nor top speed, then it will be fine.

For a single, too bad Yamaha still doesn't have a 4 stroke product to offer and looks like they never will. The F350 may be an overkill.
Suzuki does, the Zuke 300. Several modern 2 stroke options.

BirdRock · Jun 30, 2008

We have a 04 300 HPDI 2 stroke on our gulfstream. Previously had a 250 2 stroke until it died. Boat is slipped 24/7, has bottom paint and is cleaned every 3 weeks in the summer months. Numbers go something like this with an average load.

4400 rpms burning 16gph - around 27 knots
4000 rpm burning 12-13gph - around 21 knots

We definitely like the extra 50hp with the larger engine and couldn't imagine the boat with a 225 on it. If you run it empty and light it probably wouldn't be too bad but with 4 guys, fuel, ice, gear I bet it would be a dog.

Love the boat but would probably hold out for one with twins or at least a 300 on it. I wish we had twins.

Kenlahr · Jul 1, 2008

I had a 2002 with a single 225 2-stroke. Overall I was happy with the performance, but I did have to run her hard. Cruse was between 4300 and 4800 rpm, 23 to 28 kts. She really ran best between 4700 and 4800 rpm. The Gulfstream with singles response exceptionaly well to the trim tabs and we could run harder and faster than lots of other boats in poor sea conditions. WOT was 5500 rpm for me and with a load as you described I would top out at about 35 to 37 kts, never had it 40 or over in even the best of conditions. My fuel burn at 4300 was around 15 gph, at 4800 depending on conditions it would range between 17 and 19 gph.
-
As you would expect, sluggish performance would be experienced on our off shore runs, loaded with gas, a few hundred pounds of ice, a tun of gear and four men. We were a dog running out, usually only making about 20 to 23kts. We would burn off the main tank first, leaving about 25 gallons in her before switching to reserve, to keep some of the weight centered; which made the ride home better. Running home, we were much lighter and the boat performed very well. We could usually run back to OC at 28kts burning less than 19 gph.

bulldog2 · Jul 2, 2008

Pretty much what Kenlahr said,I run a 2000 with a 225 Optimax and I cruise 4600 22-24 Knots 12-13 gph and performance is not disappointing but this hull is at its best with twin 200's.Running at that RPM Contrary to popular opinion does not wear the motor out usually its just the opposite low rpm carbons the hell out of the motor and shortens the life.Pat L

Kenlahr · Jul 2, 2008

I agree; My OX66 was running outstanding when I let her go. The surveyor was very impressed with the numbers he generated considering sh had around 1200 hours. I keep the lower unit filled with fresh oil. I make it a practice to top off the lower units before heading out on every offshore run, pushing out about 1/2 cup of oil each time. Then I drain and replace it all every 100 hours. I think the moters can run at those RPM's but ya gota take care.

generalee · Jul 2, 2008

Thanks again for all the thoughts and experience. I probably do have a tendency toward overpower. Not so much for speed as much to ensure the power plant is not over tasked and that extra power is available when needed. I presently own a 23 Proline with 200 Yamaha 2 stroke (carb). I am accustomed to a "sweet spot" at approx 4000 - 4200 RPM, 28 -30 mph cruise, 10 - 10.5 gph. I realize there is a lot more hull surface area contacting the water and more weight with the Gulfstream. I want to make sure I do have adequate power for the Gulfstream to perform well operating in the engines efficient RPM range. The information provided here has answered a lot of my questions. Now - I need to find the right boat at the right price.

Challenge · Jul 2, 2008

Hello,

I have a 1998 Gulfstream w/a 250hp ox 66, It is slightly underpowered when it gets sloppy and I have to try and keep it just on plane. My performance numbers are around (By Memory):

3500 RPM 22-25 Mph 10-12 GPH
4000 RPM 29-32 MPH 15 GPH - trimmed out best cruise 2.2 MPG
4500 RPM 35 MPH around 2mpg
5000 RPM 37 MPH around 22 GPH around 1.7 MPG
5600 RMP 40-41 MPG around 30 GPH - Trimmed way out.

I think if I were to re-power I would look to the evinrudes either 250 or 300hp I've heard good things about them.

Grady doesn't honor the warranty w/a 350hp unless it is an 2008 boat.

I'm actually looking at possibly changing boats sometime soon, PM me if you have an interest.

I hope this helps

Rick

ElyseM · Jul 4, 2008

i have an '02 with twin f200's. cruise at about 28 mph and 3400 rpm (around 12 gph trimmed nicely and not fighting sea conditions). tops out at about 50 mph and 5500 rpm (w/o extreme trimout; i don't run this fast other that to blow out the engines on flat water every now and then).

rick, i specifically went for the twins (and a little overpowering) to reduce the wear on the engines. although outboards are made to run at high rpm's, as far as i'm concerned, pushing something to it's max on a consistent basis has got to have an impact over time. your inkling to go more rather than less is a good one from my perspective. ron

magicalbill · Jul 5, 2008

ElyseM is correct..
I have a 2007 with twin 200 four-strokes and performs great. I cruise at 3700-3900 and run right at 30-31 MPH.
The engines don't even breathe hard and I get 2.0-2.1 MPG.

I have powered every boat I've owned to the max and have NEVER been sorry.
I would've put 225's on it had they been offered.

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Gulfstream Power / Performance

generalee

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wlewis

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ocnslr

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catch22

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generalee

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BobP

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BirdRock

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Kenlahr

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bulldog2

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Kenlahr

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generalee

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Challenge

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ElyseM

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magicalbill

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