175 vmax on a 23 LSB SPS. The odd duck motor?

enevs22

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Hey All. New to Bennington and have a 23 LSB SPS arriving in July!

It seems like most pontoons have 150hp or f200. The 175 vmax seems to be less popular. The price difference between a 150 vmax and 175 hp vmax was like $600... seems like cheap HP Looking for a prop selection. Yamaha bulletins on tritoons with the 175 seem to run 14.5 x 14p May folks here seem to run 14.5x15p. Any other 175hp owners with a similar set up?
Thanks!
 

gotnitro

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Grats! I couldn't wait for mine to get here! I have a thread I recently posted here about props, they referred me to the prop selection bulletin at Yamaha as well. Now I'm waiting on a bigger prop to be delivered.

I was looking at all the specs on those engines when we were having ours built. They say the SHO/Vmax is hopped up with a different cams and a more aggressive tune to give them a tad more power through the RPM range and a bit more REV. When I was looking at the 150 vs the 175 the displacement and specs are exactly the same @ 2.8L I-4. I'm not sure where they are getting the extra 25 HP in a 175 unless they are using different, even more hopped up cams than the 150 cams already supposedly are. I have the 115 and they say its really 126 HP. I would assume the 150 is really somewhere around 165 HP using the same "math" they say/use for the 115. I wonder about the 175 though because using the same "math" it should be around a 200 HP but how? A 200HP SHO is a 4.2L V6. (maybe the 4.2L V-6 is detuned because the larger 225 4.2L V-6 has the same displacement) Who knows.. I'm sure torque curve and prop size along with running RPM ranges all get factored in.. My brain hurts.. I didn't look into it any farther because I couldn't fit that engine on the 21ft toon we went anyway with but I've always wondered when I see them on the lake. I have seen a few of them. Anywho, have a great year!

150 & 175
  • 2.8-liter high-output four cylinder
  • 480 lbs. dry weight
  • 20-inch and 25-inch shaft options
  • 50 amps of charging power
  • Command Link® compatibility with Variable Trolling
 

Michiman

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Hey All. New to Bennington and have a 23 LSB SPS arriving in July!

It seems like most pontoons have 150hp or f200. The 175 vmax seems to be less popular. The price difference between a 150 vmax and 175 hp vmax was like $600... seems like cheap HP Looking for a prop selection. Yamaha bulletins on tritoons with the 175 seem to run 14.5 x 14p May folks here seem to run 14.5x15p. Any other 175hp owners with a similar set up?
Thanks!
Welcome enevs22! I can't help you with your question but I can ask you to post some pictures of your new Benny when she arrives.
 

enevs22

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Grats! I couldn't wait for mine to get here! I have a thread I recently posted here about props, they referred me to the prop selection bulletin at Yamaha as well. Now I'm waiting on a bigger prop to be delivered.

I was looking at all the specs on those engines when we were having ours built. They say the SHO/Vmax is hopped up with a different cams and a more aggressive tune to give them a tad more power through the RPM range and a bit more REV. When I was looking at the 150 vs the 175 the displacement and specs are exactly the same @ 2.8L I-4. I'm not sure where they are getting the extra 25 HP in a 175 unless they are using different, even more hopped up cams than the 150 cams already supposedly are. I have the 115 and they say its really 126 HP. I would assume the 150 is really somewhere around 165 HP using the same "math" they say/use for the 115. I wonder about the 175 though because using the same "math" it should be around a 200 HP but how? A 200HP SHO is a 4.2L V6. (maybe the 4.2L V-6 is detuned because the larger 225 4.2L V-6 has the same displacement) Who knows.. I'm sure torque curve and prop size along with running RPM ranges all get factored in.. My brain hurts.. I didn't look into it any farther because I couldn't fit that engine on the 21ft toon we went anyway with but I've always wondered when I see them on the lake. I have seen a few of them. Anywho, have a great year!

150 & 175
  • 2.8-liter high-output four cylinder
  • 480 lbs. dry weight
  • 20-inch and 25-inch shaft options
  • 50 amps of charging power
  • Command Link® compatibility with Variable Trolling
Thanks! Yes its sounds like the 175 has a hotter ecu tune compared to the 150. My dealer said it should run pretty close to the f200. He said the vmax 175 makes 192hp.
 

Mozekian

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Thanks! Yes its sounds like the 175 has a hotter ecu tune compared to the 150. My dealer said it should run pretty close to the f200. He said the vmax 175 makes 192hp.
This I what I have found from my Vmax 175. I was told by many that a 175hp would get me high 30s, maybe 40 in ideal setup, on the 175hp. I have had it low 40s under "non perfect" WOT. I think if I made some drag modifications and wind favorability, I could get a few more mph out of it.

So to the original point, I love the 175Vmax. Its a few dollars more than the 150 and performs like a standard 200hp. I labored on what size engine to get to fit my needs and it seems I guessed correctly.
 

Outbackeagle

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I have a sx23 premium with the SPS package with a Vmax 175. Loaded with 6 people in windy conditions I was at 38 mph and had more throttle to go. I had to stop because my Lilly pad floating mat on the bow flew up. I'm just 5 hrs into my break in. I think I'll be in the 44 mph range with a light load and calm water I have a 14.5x15 stainless prop that was dealer installed. The motor has great throttle response and power. So far I'm pleased. I'm going from a 60hp 2 toon boat so this is a different animal all together. Plus the vmax looks better in my opinion.. Good luck with your boat!
 

enevs22

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Welcome enevs22! I can't help you with your question but I can ask you to post some pictures of your new Benny when she arrives.

This I what I have found from my Vmax 175. I was told by many that a 175hp would get me high 30s, maybe 40 in ideal setup, on the 175hp. I have had it low 40s under "non perfect" WOT. I think if I made some drag modifications and wind favorability, I could get a few more mph out of it.

So to the original point, I love the 175Vmax. Its a few dollars more than the 150 and performs like a standard 200hp. I labored on what size engine to get to fit my needs and it seems I guessed correctly.
Awesome news! Super pumped for the boat!
 

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enevs22

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I have a sx23 premium with the SPS package with a Vmax 175. Loaded with 6 people in windy conditions I was at 38 mph and had more throttle to go. I had to stop because my Lilly pad floating mat on the bow flew up. I'm just 5 hrs into my break in. I think I'll be in the 44 mph range with a light load and calm water I have a 14.5x15 stainless prop that was dealer installed. The motor has great throttle response and power. So far I'm pleased. I'm going from a 60hp 2 toon boat so this is a different animal all together. Plus the vmax looks better in my opinion.. Good luck with your boat!
Awesome. I sold a 2003 odyssey with a 90hp two stroke last season so it will be a big change for us too! Thanks for the prop thoughts.
 

SeaDog SC

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Interesting that the Yamaha 150, 175, and 200 are all exactly the same motor. Same bore stroke, same gear ratio, same weight, same size. The engineers at Yamaha just modify the ECU with chips to get the HP. The 4 cylinder VMAX SHO's list a minimum of 89 octane, which is different from the non-sho's, if your local marina only carries 87 might be an issue for you.
I would assume, after the warranty expires, if you want to boost your HP fine someone to reprogram or replace that chip in the ECU.
 

enevs22

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I have a couple 6 gal race cans. I was thinking I would run rec fuel which is 90 octane. Not sure if its needed in the new motors?
 

gotnitro

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Not at all. Going to a higher octane will only cost you more money. You might even see a slight decrease in punch as higher octane burns slower. Some seem to think more octane makes anything faster and burns cleaner, not the case and especially not the case if the compression is not there. As for 87 vs 89 for a SHO, I've burned 3 tanks of 87 and no ping at all.
 

enevs22

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Not at all. Going to a higher octane will only cost you more money. You might even see a slight decrease in punch as higher octane burns slower. Some seem to think more octane makes anything faster and burns cleaner, not the case and especially not the case if the compression is not there. As for 87 vs 89 for a SHO, I've burned 3 tanks of 87 and no ping at all.
I was thinking that rec fuel does not contain ethanol which is really bad for older motors.
 

Potomacbassin’

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The SHO motors run 89 as they advance timing amongst other things for greater torque and fatter powerband. It's also speculated that all SHO models run higher peak HP than their F counterparts. If you run 87 the ECU will pull timing and you'll be making less power.

If you don't take advantage of the SHO's capabilities you might as well get the regular F motor, save a little $ and have the ability to get digital controls instead of mechanical.
 

gotnitro

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The SHO motors run 89 as they advance timing amongst other things for greater torque and fatter powerband. It's also speculated that all SHO models run higher peak HP than their F counterparts. If you run 87 the ECU will pull timing and you'll be making less power.

If you don't take advantage of the SHO's capabilities you might as well get the regular F motor, save a little $ and have the ability to get digital controls instead of mechanical.

You are correct.

Not to split hairs but the knock sensor will only send the ECU signals every 1200-1300 RPM (to advance or retard timing) and typically stops over 6k as its already revving too fast for detonation to happen. Can you see power loss and gain using 87 to 89 octane on a data logger? Probably. Will you feel the difference while using your toon? Maybe placebo but most likely not.

If you are worried about octane, buy some octane boost OR bring your own fuel if 87 is only offered along your lakes. ;):cool:
 

Potomacbassin’

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You are correct.

Not to split hairs but the knock sensor will only send the ECU signals every 1200-1300 RPM (to advance or retard timing) and typically stops over 6k as its already revving too fast for detonation to happen. Can you see power loss and gain using 87 to 89 octane on a data logger? Probably. Will you feel the difference while using your toon? Maybe placebo but most likely not.

If you are worried about octane, buy some octane boost OR bring your own fuel if 87 is only offered along your lakes. ;):cool:

The story on the SHO (not sure if true) is that Yamaha developed it to compete with the 2-strokes from Merc and Evinrude in the bass boat crowd. The holeshot on their 4 strokes was noticeably slower, and in tournaments part of the game is getting to your honeyhole before your competitors so Yamahas were getting walked there as well. Enter the SHO where the 250hp is really 260-280 according to some posts I've read.

I tend to believe this for two reasons - 1) the SHO started off only being offered in a 20" shaft which would only target bass boats and maybe small aluminums and skiffs. And 2) most of the marketing for the SHO that I recall seeing was in bass magazines and around the tournament trails.

All this to say, if running 87 my guess is you would not only feel a difference but see a noticeable lower top speed. Maybe not night and day, but enough that would make it worth paying the extra 20 cents/gal. If 89 isn't available then I don't see the rationale in buying an SHO motor - maybe resale?

Check out this video below where they run a 250 SHO vs F300. Pretty impressive. I doubt the standard F250 could do that.

 

gotnitro

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The story on the SHO (not sure if true) is that Yamaha developed it to compete with the 2-strokes from Merc and Evinrude in the bass boat crowd. The holeshot on their 4 strokes was noticeably slower, and in tournaments part of the game is getting to your honeyhole before your competitors so Yamahas were getting walked there as well. Enter the SHO where the 250hp is really 260-280 according to some posts I've read.

I tend to believe this for two reasons - 1) the SHO started off only being offered in a 20" shaft which would only target bass boats and maybe small aluminums and skiffs. And 2) most of the marketing for the SHO that I recall seeing was in bass magazines and around the tournament trails.

All this to say, if running 87 my guess is you would not only feel a difference but see a noticeable lower top speed. Maybe not night and day, but enough that would make it worth paying the extra 20 cents/gal. If 89 isn't available then I don't see the rationale in buying an SHO motor - maybe resale?

Check out this video below where they run a 250 SHO vs F300. Pretty impressive. I doubt the standard F250 could do that.


So, is the 300 detuned? Both of those engines have the same displacement and they looked pretty dead on to me.
 

Potomacbassin’

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So, is the 300 detuned? Both of those engines have the same displacement and they looked pretty dead on to me.
Yamaha can make whatever power they want in that 4.2L V6 block since they have anything from 200 to 300 HP between the VF and F lines, ECU is the only difference (perhaps save for a few other internals with the VF). I don't think that 300 is as much detuned as the VF250 runs that close to a 300! I think that's why so many owners love them, they perform great for the $$. Both run 89, and now that the new SHO runs a 70A alternator it's possible the VF can be looked at as a slightly detuned 300.

If Yamaha allowed the digital controls on the SHO I don't see any reason it wouldn't steal every F300 sale.
 

PartyBarge

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I haven't checked on the particular motors mentioned in this thread, but some manufactures use more than just changes in spark/fuel/cam mapping for the different ratings. Tweaks to intake/exhaust manifolds and different fuel injectors are sometimes differences that are not obvious until specific part numbers are compared. Simply installing the same cam a few degrees advanced (or retarded) can have an intended and useful effect on the power/economy curves too.

Also, sometimes peak HP exceeds the number on the cowling because the manufacturer is looking to make the rating good across the entire desired RPM range, not just at the peak output.
 
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BobbyZ

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I have a sx23 premium with the SPS package with a Vmax 175. Loaded with 6 people in windy conditions I was at 38 mph and had more throttle to go. I had to stop because my Lilly pad floating mat on the bow flew up. I'm just 5 hrs into my break in. I think I'll be in the 44 mph range with a light load and calm water I have a 14.5x15 stainless prop that was dealer installed. The motor has great throttle response and power. So far I'm pleased. I'm going from a 60hp 2 toon boat so this is a different animal all together. Plus the vmax looks better in my opinion.. Good luck with your boat!
I have same exact boat motor and prop. What mounting hole are u in on engine? Top hole or next one down?
 
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