Grady White 255 w 300hp Yamaha opinions

snappa

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Hello,

Looking to hear from people that own the GW 255 powered with a Yamaha 300hp engine. Do you feel this is a good match performance wise? If you had it to do over again would you go up to the 350? Will be boating in Buzzards Bay / Vineyard Sound. I just want to make sure that this motor is the right match for the boat as I don't forsee repowering a new boat anytime soon.

Reading specs and bulletins are fine but I'm interested in people that actually own and use the 255 with a 300hp Yamaha.

Thanks in advance.
 

family affair

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Likely because you asked for 1st hand experience with that model is the reason for no response.

I'm confident few if anyone will tell you a 300 is inadequate for that hull. Going to the 350 v8 opens a whole new can of worms. Most of those worms will not make it a worthwhile option.
 

snappa

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Thanks. I'm going to water test it next week if the weather cooperates.

I've heard nothing but great things about the Yamaha 300. I posed the question mainly because of the "Top Recommended RPM" in the Yamaha performance bulletin being in the 5000-6000 RPM range. Just didn't want to go underpowered and run the engine too hard limiting its lifespan. This is due to my lack of experience running this setup. The 350 is supposed to be a great motor albeit not without its know flywheel issues that I'm hoping are fixed. My goal is to go with the 300 as I believe for my use in the area I'll be boating that this motor should be plenty of power for this setup. Really looking forward to this boat as I've waited a long time to be able to do it so just trying to make sure I "get it right" the first time.

family affair said:
Likely because you asked for 1st hand experience with that model is the reason for no response.

I'm confident few if anyone will tell you a 300 is inadequate for that hull. Going to the 350 v8 opens a whole new can of worms. Most of those worms will not make it a worthwhile option.
 

family affair

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Correct me if I'm wrong, but I think you are misinterpreting what the recommended top rpm range is. The recommended top rpm range for the engine is what the engine should be turning wide open. It is not the recommended operating engine speed.

Unless you plan to run the boat several hundred hours a year (few ever do) you won't wear out an f300 in your lifetime if you are running the engine in the typical cruise rpm (not wide open).

The flywheel issue of the v8 is still not fixed.
 

wahoo33417

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Snappa: I have the same hull in a Journey 258 powered with the Yamaha F300. It is plenty of power for what I use it for. I keep the fuel tank (127 gal.) 2/3 full or better but don't typically fill the boat with more than four people. Boat hops up on plane easily. Most importantly to me, she readily climbs the back of a following sea, allowing me to adjust my position on a wave, when I get caught running a nasty inlet.

I intentionally have her a bit over-propped so I top out at about 5400-5500 rpm and 44-45 mph. But I get an honest 3 mpg at cruise on calm water and I just don't run her higher than 4,000 rpm unless absolutely necessary. Not suggesting you prop her this way, just relaying what I get in my situation. We have about 800 hours on her and she has been flawless.

Previously, we had an F250 on our Journey. We put 1300 hours on that oengine also without a hiccup. With the F250, we could feel some sluggishness to get on plane when we had four SCUBA divers and their gear. We don't feel that with the F300.

Hope this helps.

Rob
 

snappa

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Thanks people, appreciate the input. Really looking forward to taking it out.
 

snappa

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Test drove the 255 yesterday. In short, the boat handled very well. The conditions on Buzzards Bay were unusually calm. Was hoping to get it out in the chop which is more the norm. That said, I was able to get a great test drive.

The boat topped out around 40/41mph. Not sure if it wasn't setup or possibly governed but I didn't see the RPMs get to 6k so I need to check on that. It did not feel fast but then again with the curtains up you didn't get the wind component added in. Temp was around 50 and it was very comfortable with the curtains up. I was looking for chop so I put the boat into a tight turn and generated my own. The boat went through it very smoothly. It also tracked extremely well. No slide at the stern at all. I was able to find a barge and went over its wake and still a smooth ride.

The boat got on plane at all speeds very well. Putting the throttle all the way down the bow stayed low and level.

Loved the ride overall. Would I have liked a bit more speed? Sure. Would I be able to take advantage of that speed on BB most days? No.
 

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bea5454

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Congratulations, looks great. Wish I could have been out there yesterday.

Curtains up (bottom paint?) I would think 40-42 mph is probably about right. What RPM were you able to hit as propped?

You are definitely correct that small boats in the 40's and BB don't mix all that frequently. Best of luck with her!
 

Rustygaff

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I think the 255 with the F300 is stock propped with a 15 x 15 3/4 SDS. I also do not recall seeing 6000 RPM's at WOT on my boat which is ablative bottom painted. I am also OK with getting low 40's at WOT. I cruise mostly inside Fisher's Island or over to Block and rarely need or wish to go any faster due to water conditions. If it was built to run like a Regulator, different story. IMHO, the 255 with the F300 performs well for what it is. A comfortable heavy day fishing/cruising vessel for us old guys :)