2520 XL with new Suzuki 300

[BlackRoee]

Hi. I’m hearing speeds guys are getting on their boats and something doesn’t add up with me. I’m curious as to what other guys are seeing. Here is what I have.

2004 2520xl with 2021 suzuki 300 (4 stroke) on Armstrong bracket with one more hole it could be lowered. I usually run it with a full tank of gas as I run offshore 30-50 miles on my charters. I have a Suzuki 3x16x18.5 stainless prop.

whether I have a full boat or one other person, the top speed won’t go above 31 mph. But the big difference is the inability to get on plane quickly. Even light, it’s tough getting on plane quickly and with a full load, in heavy seas, it could take a couple of minutes!

I don’t know how much is wrong or what to expect. Any help is appreciated. What are other 2520 owners with 300 hp seeing for numbers and what are you running for props/engine placement?

 

[Kendall Brown]

When you are up on plane where is the cavitation plate? If it’s below the surface you are sitting to deep on the bracket and adding a lot of drag.
What is the WOT RPM rating for the engine and what are you seeing for max RPM?

 

[Deadrise36]

Running an F-300 on a 2020 2520 with an OFS4 (four blade) 15 pitch x 15 1/4. I'm getting 40 mph at 6000 rpm, 5 bars of trim, 26 gph, flat water. She hops up on plane in a few second - half tank, two people. What is you max rpm?

 

[Deadrise36]

Engine is mounted as low as it can go

 

[baker]

Running an F-300 on a 2020 2520 with an OFS4 (four blade) 15 pitch x 15 1/4. I'm getting 40 mph at 6000 rpm, 5 bars of trim, 26 gph, flat water. She hops up on plane in a few second - half tank, two people. What is you max rpm?

"...5 bars of trim..." engine or tabs? What is your mpg at WOT and mpg at normal cruise?

 

[Deadrise36]

"...5 bars of trim..." engine or tabs? What is your mpg at WOT and mpg at normal cruise?

Max: 1.5 mpg 6000 rpm - 40 mph - 6 bars engine trim
Cruise: 2.3 mpg 4200 rpm - 29 mph - 4 bars engine trim

 

[baker]

Max: 1.5 mpg 6000 rpm - 40 mph - 6 bars engine trim
Cruise: 2.3 mpg 4200 rpm - 29 mph - 4 bars engine trim

Those numbers are fantastic. I hope to achieve the same when I receive the OFS4-15 prop I ordered 7 weeks ago.

 

[Deadrise36]

Those numbers are fantastic. I hope to achieve the same when I receive the OFS4-15 prop I ordered 7 weeks ago.

I think you will find it worth the wait. I waited 7 weeks for an OFS4-16 that it did everything I had hoped except for only getting 5500 rpm wot. Sent it back and got the 15 in short order. I haven't put much time on the 15 yet, but both OFS4 props give noticeable stern lift, better bight going astern, hold plane around 14-15kts and lessened vibration at slow speed over the 3 blade 17-T 15 1/2 Yamaha prop that I started with. I was was getting 5700 with the Yamaha prop and am now getting 6000 with the OSF4 15. I lost a few mph of the top end and am getting slightly less mpg but it's only a few tenths.

 

[Swatski]

I think you will find it worth the wait. I waited 7 weeks for an OFS4-16 that it did everything I had hoped except for only getting 5500 rpm wot. Sent it back and got the 15 in short order. I haven't put much time on the 15 yet, but both OFS4 props give noticeable stern lift, better bight going astern, hold plane around 14-15kts and lessened vibration at slow speed over the 3 blade 17-T 15 1/2 Yamaha prop that I started with. I was was getting 5700 with the Yamaha prop and am now getting 6000 with the OSF4 15. I lost a few mph of the top end and am getting slightly less mpg but it's only a few tenths.

I am patiently waiting for my OFS4 15 from Ken. Been a couple of months now.
Your report is very encouraging in every aspect, as this is what would hope to see when I do the swap, 2021 2320 with F300.

I should clarify, the factory prop actually works great in flat water, it's outstanding really - 5,900 and 50mph.
But offshore chop is a different story (NJ).

--

 

[BlackRoee]

Running an F-300 on a 2020 2520 with an OFS4 (four blade) 15 pitch x 15 1/4. I'm getting 40 mph at 6000 rpm, 5 bars of trim, 26 gph, flat water. She hops up on plane in a few second - half tank, two people. What is you max rpm?

How is the boat with a full tank and five people? In a sloppy sea?

 

[Mpellet]

Hi. I’m hearing speeds guys are getting on their boats and something doesn’t add up with me. I’m curious as to what other guys are seeing. Here is what I have.

2004 2520xl with 2021 suzuki 300 (4 stroke) on Armstrong bracket with one more hole it could be lowered. I usually run it with a full tank of gas as I run offshore 30-50 miles on my charters. I have a Suzuki 3x16x18.5 stainless prop.

whether I have a full boat or one other person, the top speed won’t go above 31 mph. But the big difference is the inability to get on plane quickly. Even light, it’s tough getting on plane quickly and with a full load, in heavy seas, it could take a couple of minutes!

I don’t know how much is wrong or what to expect. Any help is appreciated. What are other 2520 owners with 300 hp seeing for numbers and what are you running for props/engine placement?

Our boats are very similar. I have a transom mounted 2005 Parker 2520 with a 2019 Suzuki DF300APXX. I run my boat just like yours, always offshore, typically start with fuel tank at 150 gallons. My boat never has a problem getting on plane, my top speed in very smooth water is about 33 knots at 6000 RPM when I have time to get it all trimmed up .

Keep in mind I run in nautical miles not statute.

I have a friend with same engine and boat as you. I don’t know what propeller he is running but his numbers are similar to mine.

Your top end speed seems a little slow but not awful but the slow to get on plane does seem off to me. That was the most apparent performance improvement I noticed going from a Yamaha F225 to the Suzuki DF300APXX was how fast the boat got on plane with the new engine. Snaps right up on plane regardless of weigh.

I have a 3 Blade Suzuki Propeller and I am also slightly embarrassed to confess that I can’t recall pitch or size off the top of my head but I can get back to you with propeller specifications if you want.

 

[mrtodds]

2004, 2520XL, MV, 2019 Suzi 300 one hole up from bottomed out, 3-16-17 watergrip. 41 wot with 3/4 tank and 5 adults, cruise 32 at 4400. "Getting it up"; Before launching motor all the way down, trim tabs 3 seconds down, full throttle. At 18MPH I raise tabs while adjusting motor trim for max speed at throttle setting. This is just what I do and I think should be done with respect to tabs etc. , I've run into people who never knew the tabs help in a launch so I figured I'd cover that. I plane almost immediately, to about 30 seconds depending on load, light load ya better hang on tight! Your prop at 18.5 is what I started with, you're overpitched.

 

[Mpellet]

2004, 2520XL, MV, 2019 Suzi 300 one hole up from bottomed out, 3-16-17 watergrip. 41 wot with 3/4 tank and 5 adults, cruise 32 at 4400. "Getting it up"; Before launching motor all the way down, trim tabs 3 seconds down, full throttle. At 18MPH I raise tabs while adjusting motor trim for max speed at throttle setting. This is just what I do and I think should be done with respect to tabs etc. , I've run into people who never knew the tabs help in a launch so I figured I'd cover that. I plane almost immediately, to about 30 seconds depending on load, light load ya better hang on tight! Your prop at 18.5 is what I started with, you're overpitched.

The 32 at 4400 is an amazing #. I’m not even close to that.....

 

[BlackRoee]

When you are up on plane where is the cavitation plate? If it’s below the surface you are sitting to deep on the bracket and adding a lot of drag.
What is the WOT RPM rating for the engine and what are you seeing for max RPM?

I can trim it waAay up and get the rpm to 5900 rpm, but speed doesn’t increase at all

 

[MURPH]

Our boats are very similar. I have a transom mounted 2005 Parker 2520 with a 2019 Suzuki DF300APXX. I run my boat just like yours, always offshore, typically start with fuel tank at 150 gallons. My boat never has a problem getting on plane, my top speed in very smooth water is about 33 knots at 6000 RPM when I have time to get it all trimmed up .

Keep in mind I run in nautical miles not statute.

I have a friend with same engine and boat as you. I don’t know what propeller he is running but his numbers are similar to mine.

Your top end speed seems a little slow but not awful but the slow to get on plane does seem off to me. That was the most apparent performance improvement I noticed going from a Yamaha F225 to the Suzuki DF300APXX was how fast the boat got on plane with the new engine. Snaps right up on plane regardless of weigh.

I have a 3 Blade Suzuki Propeller and I am also slightly embarrassed to confess that I can’t recall pitch or size off the top of my head but I can get back to you with propeller specifications if you want.

I have exactly the same boat and motor as you but only get 5600. Curious to know what size prop you are running

 

[BlackRoee]

2004, 2520XL, MV, 2019 Suzi 300 one hole up from bottomed out, 3-16-17 watergrip. 41 wot with 3/4 tank and 5 adults, cruise 32 at 4400. "Getting it up"; Before launching motor all the way down, trim tabs 3 seconds down, full throttle. At 18MPH I raise tabs while adjusting motor trim for max speed at throttle setting. This is just what I do and I think should be done with respect to tabs etc. , I've run into people who never knew the tabs help in a launch so I figured I'd cover that. I plane almost immediately, to about 30 seconds depending on load, light load ya better hang on tight! Your prop at 18.5 is what I started with, you're overpitched.

It might take two minutes to get up on plane like that. I’ll try changing props!

 

[Efx]

I would check if you have the engine too low or the wrong size, like a 30”. Something seems very off. What are the max rpms?

 

[BlackRoee]

I would check if you have the engine too low or the wrong size, like a 30”. Something seems very off. What are the max rpms?

I can trim it way up and get it to 5900

 

[Mpellet]

I have exactly the same boat and motor as you but only get 5600. Curious to know what size prop you are running

 

[Efx]

I can trim it way up and get it to 5900

Is the 5900 cavitation? Or has complete grip?