Forced induction

I have the 23' Yamaha svho in a Yamaha Center Console 19' fish boat.
It is a supercharged 4cylinder 250hp inboard jet boat,
Supercharger requires no extra maintenance.
I can run in the valley, Roosevelt or Lake Powell without making any mechanical changes and have great performance.
Cruise, 32mph at 6000 rpm, 1300ft asl. Cruises, 28mph at 6000 rpm at Lake Powell.
yamaha-waverunners-2022-pdp_featuregallery-engine.jpg

I removed the tower and replaced it with an 8' bimini, I also added a pedestal fish seat to the bow.
file photo...
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That picture of your engine is a thing of beauty to me! Leave it to the Japanese, Gear driven supercharger right out front, DOHC, Coil packs dead center up top (looks like a hemi head) wet sump oil system, common rail injection. You can spot all that just from the photo.

Back in the 60's it was a big milestone for power when an engine first had one HP for every cubic inch, 327/327. I looked it up and this engines displacement is just 1.8 liters and that equals only about 100 cubic inches of displacement. So that is almost 2.5 hp for every cubic inch. That's bonkers good on pump gas plus it's Yamaha so it's going to be reliable
 
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I just traded my 2019 Tundra 1794 V8 in on a 2024 Tundra 1794 with a twin turbo V6 with the iMax Hybrid. This truck is light years ahead of my previous Tundra. I towed my 18 foot Ranger VX1788 to Lake Powell last weekend and I was really shocked on how everything worked compared to the V8, This truck has the electric motor between the twin turbo V6 and a 10 speed transmission. In tow mode, as I drove from Scottsdale uphill to Lake Powell, the electric iMax motor kicks in without sound at whatever speed you want to do in cruise but you don't have the engine rev noise at all. In fact, I couldn't believe that I was flying uphill at 75-80 mph at 1800-2000 rpm. My boat and trailer weigh 4200 pounds. The torque on this truck is 580 foot pounds with 440 hp. It towed like a dream and and I got 14.4 mpg with a fully loaded truck and 3 guys. For some reason, I thought that the primary purpose of the Hybrid was gas mileage, and that's true, but it's really about power and taking the effort off of the engine. Even more surprising, I couldn't detect any shifting, hearing or feeling, by the transmission. On downgrades, I shifted into manual but on the way home, i just put it in cruise and adjusted the speed to the downgrade. The truck did the rest. The truck has technology to back directly up to the hitch which worked perfectly and, similar to the F-150, it will back straight down into the water but I can't bring myself to trust that technology just yet. The ride and handling of the new Tundra is vastly superior to my old Tundra. And, the fishing was pretty good too. We went into the back of Navaho Canyon the first day. The Stripers were scattered much more than I expected, but using Livescope, we still caught 20-30 Stripers, many 4-5 pounds. All of them were full of Shad. It was a full moon and I think that the Stripers were feeding mostly at night. The second day we went into Rock Creek Canyon and we caught another 20-30 Stripers but we had to work hard for them. Again, the Stripers were really healthy and big, but not hungry. I could see my bait on Panoptics, and many Stripers would charge it, even slap it with their tail, but they would not take it. My fishing buddies saw this too. It's pretty amazing to see what the fish do relative to a bait. I located a school of 200 plus Stripers and dropped my bait right on to them in 25 feet of water. Many Stripers came right to the bait but just turned away. We didn't catch a single fish out of that school. That's never happened to me before, proving that, despite the best technology, that fish can get the last laugh. That's why they call it fishing instead of catching. That said, the Striper filets were awesome :)
 
Just closing this out. Thanks for those who responded.

I REALLY wanted the boat I found with a 200 Yamaha. But we couldn’t come together on a price we both could live with. I ended up with a 175 Verado. I’ve had it on the water twice and so far I’m pretty impressed.

Hopefully I’ll get it on Powell in the next couple of months. Will be interesting to see how much different (if at all) it performs at lower elevation.
 
Just closing this out. Thanks for those who responded.

I REALLY wanted the boat I found with a 200 Yamaha. But we couldn’t come together on a price we both could live with. I ended up with a 175 Verado. I’ve had it on the water twice and so far I’m pretty impressed.

Hopefully I’ll get it on Powell in the next couple of months. Will be interesting to see how much different (if at all) it performs at lower elevation.
You can also send the ECU on the Verado in to have it programmed up to 225hp
 
I did a little (very little) google search. From what I found, reprogramming the ECM in the Verado was a fairly common practice until someone cracked down on it (some threads say Merc, some say EPA). Anyway, I can’t find anything recent about being able to do it.

I hope I’m wrong. Who wouldn’t want a tune for some additional power?
 
Yes the EPA has been cracking down on tuning providers. Tuning can be questionable for cars and trucks, IDK about a marine engine. You are altering the timing and fuel mixture pretty dramatically in most cases with radical tunes. In light weight Diesel trucks, a very commonly tuned vehicle, I've seen guys destroy their motors by running hot tunes and raising the Exhaust Gas Temps into the stratosphere.

Personally, I'm kinda of the opinion that in most cases the engineers set the parameters of the computers up for power and longevity. In making big power gains(fun stuff) with radical tunes you will usually give up reliability and longevity. The more hopped up a motor the less reliable it becomes. If it were me I'd see how the awesome supercharged setup with 175 HP treated me, if that wasn't enough, before I modified anything. I think reliability is a huge priority for a single engine boat out on Powell. It's not like a truck on the road where when you blow it up you just coast off the road and call AAA.
 
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Yes the EPA has been cracking down on tuning providers. Tuning can be questionable for cars and trucks, IDK about a marine engine. You are altering the timing and fuel mixture pretty dramatically in most cases with radical tunes. In light weight Diesel trucks, a very commonly tuned vehicle, I've seen guys destroy their motors by running hot tunes and raising the Exhaust Gas Temps into the stratosphere.

Personally, I'm kinda of the opinion that in most cases the engineers set the parameters of the computers up for power and longevity. In making big power gains(fun stuff) with radical tunes you will usually give up reliability and longevity. The more hopped up a motor the less reliable it becomes. If it were me I'd see how the awesome supercharged setup with 175 HP treated me, if that wasn't enough, before I modified anything. I think reliability is a huge priority for a single engine boat out on Powell. It's not like a truck on the road where when you blow it up you just coats off the road and call AAA.
I agree with your assessment of tuning and the compromises between performance and longevity. However, I am not sure this applies to the Verados. They sold them as 135, 150, 175 and 200’s. The same engines with different tuning. Not really sure the 200 is any less reliable than the 135?
 
Yes the EPA has been cracking down on tuning providers. Tuning can be questionable for cars and trucks, IDK about a marine engine. You are altering the timing and fuel mixture pretty dramatically in most cases with radical tunes. In light weight Diesel trucks, a very commonly tuned vehicle, I've seen guys destroy their motors by running hot tunes and raising the Exhaust Gas Temps into the stratosphere.

Personally, I'm kinda of the opinion that in most cases the engineers set the parameters of the computers up for power and longevity. In making big power gains(fun stuff) with radical tunes you will usually give up reliability and longevity. The more hopped up a motor the less reliable it becomes. If it were me I'd see how the awesome supercharged setup with 175 HP treated me, if that wasn't enough, before I modified anything. I think reliability is a huge priority for a single engine boat out on Powell. It's not like a truck on the road where when you blow it up you just coats off the road and call AAA.
Agreed on a lot of what you say, but not all of it. There are cases where a manufacturer uses a lower power tune simply as a differentiator in engines (and a reason to charge more for it). For example, in 2015 Malibu boats used the same engine to get different HP levels - one was 410 and one was 450. Torque change was even more dramatic. A friend did an in-depth search and could find nothing different in the two engines other than the tune.

Again, I have only done minor research, but it seems that the 175 Verado and 225 were the same other than the tune. It also sounds like it was true on some of the higher HP motors - same displacement, cams, pistons, different tune to get more power (possibly at the sacrifice of requiring higher octane).

I ran a different tune on my 2003 Cummins for two years with no ill effects. I had a custom tune installed in my 2012 (that one was even emissions compliant). Both of those tunes had a SIGNIFICANT increase in power - the 03 could crest Eisenhower tunnel at over 10 MPH faster than stock when towing 15000 pounds. I haven’t done anything nor do I plan to on my current truck because I don’t feel the need for additional power.

And I completely agree on the reliability factor. The last thing I want on vacation is to have something that I can’t count on - especially in Good Hope Bay in the offseason with no phone service and very few boats around.

So I need to do more research, and weigh the trade-offs, but a custom tune isn’t something I personally would disregard off hand.
 
I agree with your assessment of tuning and the compromises between performance and longevity. However, I am not sure this applies to the Verados. They sold them as 135, 150, 175 and 200’s. The same engines with different tuning. Not really sure the 200 is any less reliable than the 135?
Really, no difference in displacement? IDK about that? That's a tesla deal, one electric motor different computer profiles. I guess it's possible but combustion engines are very different than electric motors. I'm not a Verado expert by any means. I prefer my 200 hp Evinrude E Techs with direct injection but I'm sure they are both good motors
 
Agreed on a lot of what you say, but not all of it. There are cases where a manufacturer uses a lower power tune simply as a differentiator in engines (and a reason to charge more for it). For example, in 2015 Malibu boats used the same engine to get different HP levels - one was 410 and one was 450. Torque change was even more dramatic. A friend did an in-depth search and could find nothing different in the two engines other than the tune.
The Indmar Raptor engines are the same way. They offer 350 and 410 HP versions of the same engine with 404 and 452 ft-lb torque respectively. The only difference is a tuning change and they required you to run a higher octane gas through the up-tuned version. They also offer a 510 HP, 580 ft-lb torque version of the same engine but it has a supercharger. Boat engines are way easier to cool than car engines.
 
Seems like different HP outputs from one platform is the future but you won't double power output from one displacement on tuning alone. Of course if you add a supercharger to the mix all bets are off; you can underdive or overdrive them for vast differences in power. Maybe that's how Mercury gets so much difference with the Supercharged Verado, I can believe that.

Like Nzaugg said, Cooling is a big issue in cars that isn't as relevant in boats, that and pollution control devices which tend to retain heat. More combustion means more power and more heat but you've got plenty of cooling available in a lake so extreme tuning is probably more forgiving in a marine setting. Good point
 
Really, no difference in displacement? IDK about that? That's a tesla deal, one electric motor different computer profiles. I guess it's possible but combustion engines are very different than electric motors. I'm not a Verado expert by any means. I prefer my 200 hp Evinrude E Techs with direct injection but I'm sure they are both good motors
Yes, same displacement…Pretty sure Evinrude did the same thing with the e-techs…my old Mercury 2 stroke came as 75, 90, 115 and 125. All the same displacement.
 
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