Engine HP and Torque rates

[kaelc]

Further to the ongoing discussion about HP rating on Merc SeaPros this has been discussed a lot on the hull truth. One source of information is the California emissions board, it is not definitive and just used to meet one governments requirements

New Vehicle and Engine Certification: Executive Orders for MY2023 Spark-Ignited Marine Engines | California Air Resources Board

The New Vehicle and Engine Certification Program is responsible for the certification of new engines, vehicles, powertrains, aerodynamic devices and other new certifications. Vehicles and engines may be sold and otherwise produced in California only if approved by Executive Order (EO) after...

ww2.arb.ca.gov

Merc 150’s

https://ww2.arb.ca.gov/sites/default/files/classic/msprog/nvepb/executive_orders/EO%20Web%20Files/SIME/2023/0001/sime_sime_uw-1-578__sdt--20220526.pdf

 

[kaelc]

I thought that data suited the other thread quite well. Are you going to start another thread for counter rotating engines?

I spent a ton of time looking at peak torque and hp ratings for 150-200hp engines and as much as everyone wants to go into that if you are looking for a 9.9 or a 300hp this discussion is a derail

 

[macro]

Further to the ongoing discussion about HP rating on Merc SeaPros this has been discussed a lot on the hull truth. One source of information is the California emissions board, it is not definitive and just used to meet one governments requirements

New Vehicle and Engine Certification: Executive Orders for MY2023 Spark-Ignited Marine Engines | California Air Resources Board

The New Vehicle and Engine Certification Program is responsible for the certification of new engines, vehicles, powertrains, aerodynamic devices and other new certifications. Vehicles and engines may be sold and otherwise produced in California only if approved by Executive Order (EO) after...

ww2.arb.ca.gov

Merc 150’s

https://ww2.arb.ca.gov/sites/default/files/classic/msprog/nvepb/executive_orders/EO%20Web%20Files/SIME/2023/0001/sime_sime_uw-1-578__sdt--20220526.pdf

Super informative. Thank you for the link.

 

[kaelc]

Yeah peak torque and differences in torque really are intriguing to me. A friend who had bought a Merc Command Thrust and my interest in the Merc 150 producing peak torque at 3k rpm. Also the toque differences between 200hp engines and how it relates to displacement.

 

[Max123]

That's a really interesting resource.

I was looking at the Suzuki 140 vs 150hp models. Its funny because everyone says its a 'weak' 140 - but both models test almost exactly at their rated hp. The big difference is torque. The 140hp @ 168 n-m, the 150hp @ 237-249 n-m. The 140hp model also has peak torque at 4500rpm, whereas the 150hp at 4000rpm - making it that much more noticeable. 7% difference in hp, but 40% difference in torque.

If you are doing the classic comparison of 150hp models:

Yamaha 150: 121kw (162hp) / 228n-m @ 3750rpm
Mercury 150: 120kw (161hp) / 244n-m @ 3000rpm (Seapro 150 is de-tuned down to 140hp, and lower torque)
Suzuki 150: 110kw (147hp) / 237n-m @ 4000rpm (interestingly, the drive by wire 'AP' model torque is bumped up to 249n-m - not sure why)
Honda/Tohatsu 150: 112 kw (150hp) / 202n-m @ 5000rpm

Out of the box, Mercury, Yamaha, Suzuki are going to stack up similar with minor differences in how they behave (likely more based on how you use it, and the hull), but credit to the Merc for both low end grunt and peak hp. I suspect the Honda/Tohatsu would feel really weak if you did a back to back comparison with the other models on the same hull.

Anyway, interesting to see.

 

[kaelc]

That's a really interesting resource.

I was looking at the Suzuki 140 vs 150hp models. Its funny because everyone says its a 'weak' 140 - but both models test almost exactly at their rated hp. The big difference is torque. The 140hp @ 168 n-m, the 150hp @ 237-249 n-m. The 140hp model also has peak torque at 4500rpm, whereas the 150hp at 4000rpm - making it that much more noticeable.

Not entirely surprising, as most people confuse hp and torque.

That's really the biggest take away. Members have said there is no replacement for displacement and you really see that. Between the 4 cyclinder 200hp and the 6 Cyclinders 200hp engines it feels like night and day. It seems like a 20% difference in torque ratings between 200hp engines and at lower RPM. When you have a single engine on a heavy boat I feel like it could make a huge difference. My buddy bought a 200hp on his little boat and I would be so disappointed if I had paid 30k and was getting his performance.

 

[Max123]

Just to further complete the experiment, lets look at the 9.9hp motors:

Yamaha: 212cc / 7.3kw / 13.7n-m @ 4350rpm
Suzuki: 327cc / 7.3kw / 18.4n-m @ 3000rpm
Mercury: 209cc / 7.28kw / 13n-m @ 5000rpm
Honda: 222cc / 7.4kw / 13.1 n-m @ 4500rpm
Tohatsu: 209cc / 7.4kw / 14.1 n-m @ 4500rpm

Suzuki is killing it in the 9.9 class, with about 30% more torque than the next closest competitor at significantly lower rpm. Large displacement + fuel injection just makes this the stand out choice, and you don't need to rev the nuts off it to access the power. Interesting to see it in such stark terms as many people think all motors in this class are more-or-less the same.

I looked at a few other models, but the 9.9 model really stands out because of the scale of difference and because its so common (for small fishing boats or as a kicker).

 

[barkerfam]

Just to further complete the experiment, lets look at the 9.9hp motors:

Yamaha: 212cc / 7.3kw / 13.7n-m @ 4350rpm
Suzuki: 327cc / 7.3kw / 18.4n-m @ 3000rpm
Mercury: 209cc / 7.28kw / 13n-m @ 5000rpm
Honda: 222cc / 7.4kw / 13.1 n-m @ 4500rpm
Tohatsu: 209cc / 7.4kw / 14.1 n-m @ 4500rpm

Suzuki is killing it in the 9.9 class, with about 30% more torque than the next closest competitor at significantly lower rpm. Large displacement + fuel injection just makes this the stand out choice, and you don't need to rev the nuts off it to access the power. Interesting to see it in such stark terms as many people think all motors in this class are more-or-less the same.

I looked at a few other models, but the 9.9 model really stands out because of the scale of difference and because its so common (for small fishing boats or as a kicker).

do you know if that is the Tohatsu EFI?

 

[Dwaynec83]

Sorry for going off topic in the other thread,

Anybody notice how the regular merc 225 is a v6 and the seapro 225 is a v8 that actually does 234hp?

And all the new efi mercury pro kickers are 333cc, the 9.9 actually makes 19.2nm

 

[Dwaynec83]

do you know if that is the Tohatsu EFI?

Tohatsu makes mercury’s engines from 9.9 to 20

 

[Gallivanter]

That's really the biggest take away. Members have said there is no replacement for displacement and you really see that. Between the 4 cyclinder 200hp and the 6 Cyclinders 200hp engines it feels like night and day. It seems like a 20% difference in torque ratings between 200hp engines and at lower RPM. When you have a single engine on a heavy boat I feel like it could make a huge difference. My buddy bought a 200hp on his little boat and I would be so disappointed if I had paid 30k and was getting his performance.

I have a 200 Zuke 4 cylinder on my 22 footer, the fuel economy, holeshot torque, overall performance is fantastic, couldn’t be happier. 30 MPH at 4300 rpm, gets the family around nicely. Definitely not disappointed

 

[kaelc]

I have a 200 Zuke 4 cylinder on my 22 footer, the fuel economy, holeshot torque, overall performance is fantastic, couldn’t be happier. 30 MPH at 4300 rpm, gets the family around nicely. Definitely not disappointed

I would definitely take a Zuke 200. Guides and friends with tons of boat knowledge choose them!

Nice to see the kicker power as well.

 

[seahorse]

It was the best decision when I decided to hang Suzuki’s on Seafarer, thanks for confirming my choice.

 

[Thunder21]

I would definitely take a Zuke 200. Guides and friends with tons of boat knowledge choose them!

Nice to see the kicker power as well.

I am happy with my I-4 200s as well. They seem to have a good reputation. I have always had the opinion that Yamaha and Suzuki made a better engine than Merc but those Sea pros look pretty nice. Large displacement, lower rpm, more low end torque and a heavy duty gear case . I’d bet with that combo the performance difference and longevity is significant over a pair of I-4s. Particularly if you are offshore often. Larger swell and a heavily loaded boat is where you’d really notice the difference I think.

 

[macro]

That's a really interesting resource.

I was looking at the Suzuki 140 vs 150hp models. Its funny because everyone says its a 'weak' 140 - but both models test almost exactly at their rated hp. The big difference is torque. The 140hp @ 168 n-m, the 150hp @ 237-249 n-m. The 140hp model also has peak torque at 4500rpm, whereas the 150hp at 4000rpm - making it that much more noticeable. 7% difference in hp, but 40% difference in torque.

If you are doing the classic comparison of 150hp models:

Yamaha 150: 121kw (162hp) / 228n-m @ 3750rpm
Mercury 150: 120kw (161hp) / 244n-m @ 3000rpm (Seapro 150 is de-tuned down to 140hp, and lower torque)
Suzuki 150: 110kw (147hp) / 237n-m @ 4000rpm (interestingly, the drive by wire 'AP' model torque is bumped up to 249n-m - not sure why)
Honda/Tohatsu 150: 112 kw (150hp) / 202n-m @ 5000rpm

Out of the box, Mercury, Yamaha, Suzuki are going to stack up similar with minor differences in how they behave (likely more based on how you use it, and the hull), but credit to the Merc for both low end grunt and peak hp. I suspect the Honda/Tohatsu would feel really weak if you did a back to back comparison with the other models on the same hull.

Anyway, interesting to see.

Would the best motor be the one with the most torque at the lowest rpm? Warranty/weight/fuel burn/reliability aside?

 

[EZZ70]

Would the best motor be the one with the most torque at the lowest rpm? Warranty/weight/fuel burn/reliability aside?

Great question, how to decipher the data... Thank you this is really useful information and a GREAT thread... thank you for starting it.

So, it seems the ProKicker is the top choice of kickers, Suzuki being 2nd, would the 9.9 vs 15 be significant? and worth the extra $$?

 

[Max123]

Full credit to @Dwaynec83 for the correction about the 9.9 prokicker. Definitely a beast, as its a detuned version of the 9.9/15/hp motor and stacks up basically the same as the suzuki. Large displacement, loads of low end torque, EFI.

One note, the Suzuki 9.9 weights +/-97lbs and the Prokicker weights 108lbs. Compare that to the carb models such as the yamaha @ 87lbs or the Mercury @ 84lbs. No surprise, the prokicker is really meant for permanent mounting, and the Suzuki is a bit of a porker as well. The carb 9.9 models are the 'light' weights.

​

 

[ship happens]

Tohatsu makes mercury’s engines from 9.9 to 20

30hp and below

 

[EZZ70]

Sorry for going off topic in the other thread,

Anybody notice how the regular merc 225 is a v6 and the seapro 225 is a v8 that actually does 234hp?

And all the new efi mercury pro kickers are 333cc, the 9.9 actually makes 19.2nm

View attachment 102170

Hey, I just went to Mercury website, is this information on the website not updated to what @Dwaynec83 mentioned...? I just might be missing something. It doesn't mention the 9.9 to be EFI, just the 15hp.

 

[Max123]

Manufacurer	Model	cc	kW	hp	Peak Torque	Peak Torque Rpm
Honda	200​	3583​	149​	199.8​	310​	4500​
Honda	225​	3583​	168​	225.3​	315​	5000​
Honda	250​	3583​	186​	249.4​	320​	5000​
Mercury	175​	3432​	138​	185.1​	312​	4000​
Mercury	200​	3432​	149​	199.8​	314​	4500​
Mercury	225​	3432​	168​	225.3​	314​	4500​
Mercury	225​	4576​	172​	230.7​	389​	3750​
Mercury	250​	4576​	196​	262.8​	413​	4000​
Mercury	300​	4576​	221​	296.4​	424​	4500​
Suzuki	200​	2867​	147​	197.1​	249​	4000​
Suzuki	225​	3614​	165​	221.3​	312​	4500​
Suzuki	250​	3614​	184​	246.7​	314​	4500​
Suzuki	250​	4028​	184​	246.7​	343​	4500​
Suzuki	300​	4028​	221​	296.4​	357​	4500​
Yamaha	200​	2785​	146​	195.8​	258.8​	3900​
Yamaha	225​	4169​	184​	246.7​	358​	4350​
Yamaha	250​	4169​	200​	268.2​	375​	4650​
Yamaha	300​	4169​	222​	297.7​	400​	4950​