Brad M invited me to join your forum and help provide some technical help and answers to some of the questions being asked regrading Flash tuning the Yamaha 4.2 litre V6 engines and possibly our Nizpro 450s Supercharger systems.
I see Brian from Ft Myers has also come aboard and shared some of his customers results, hi Brian, great to see you posting.
I guess after reading this thread I can clearly see a number of questions and comments that need addressing, some I will be able to help with and some are simply peoples differing views about modify factory standard engines. These can never be answered with a right or wrong answer and are simply different people’s views which they are certainly entitled to, all I can do is possibly offer a different perspective.
Please let me start with the mechanical side of the discussion.
The Yamaha 4.2 litre V6 engine is a very well designed robust and an efficient power plant. All outboard engines work in a very harsh hi duty cycle environment, so there will always be an odd issue with all brands of engine, non are perfect. However Yamaha is at the pointy end of reliability, economy and performance. Some will say that if you want to go fast you must have Mercury. In many ways this is an accurate statement. Mercury for as long as I can remember ( 30 years plus ) have always developed products that are more speed focused, their marketing has always relied on race results to enforced there performance and they have really been the only manufacture that has constantly supported race series ,even to this day.
By contrast Yamaha have been very conservative, however this does not mean that they also cannot produce a performance engine. The main problem is if you want to go fast there is simply a very limited range of parts available off the shelf for Yamaha product. Props, steering, 15 inch trunks are all easily obtainable for Mercury, all the other brands up to now there has been virtually nothing available. So if you are focusing on a high speed mono or cats Mercury really has been your choice, your circles of friends have similar boats and engines, it’s all you see, but please be open minded, there are now other options becoming available. This is a hugh benefit for all outboard owners, remember competition breeds innovation.
So let’s clear this up once and for all. Are all 4.2 litre 200 though to 300 hp engine s the same?
It terms of power output all Yamaha V6 4.2 litre power heads are the same. Yes Offshore have added corrosion protection and larger charge rates. But the rotating assembly and its ability to produce a given Hp number is the same wether it has a 200,225,250 or 300 hp sticker placed on the engine cowl.
Yamaha are far from alone in both the automotive and marine industry in producing one engine series while being able to market and sell them at difference power levels. This would now be more common than not.
The change in power output is confined to Engine Management Calibration and normally done over a number of different areas within the calibration. Fuel, spark, camshaft timing and throttle opening can all be adjusted to deliver the power and torque curve needed to produce engines of different ratings to suit difference applications at difference consumer price points, while at the exact same design, tooling and manufacturing costs to the manufacture. Typically manufactures will have the model engine that is currently available in its highest power output already developing more power for an upcoming model for later release, with minimal changes required. Of course at some point the same basic architecture has a power limit within the original design scope.
So once the above is explained turning a 200 SHO or a 225 offshore into a 300 hp engine has zero impact in reliability, emissions or economy over buying a standard 300 hp engine from Yamaha in the first place.
Once you look at it in these terms and then look at our re flashing power outputs we have a 10% increase in output over standard, hardly a reliability breaker when done correctly.
Why don’t Yamaha offer a 325 hp version? The answer to this question is purely guess work.
Yamaha do have a 275 SHO for their own Japanese market, why don’t we have it? Who knows?
Why don’t they offer a 325 Offshore? Maybe they believed it would take sales from their F350 V8.
It’s not because of durability of the power head or lower unit.
Durability tests can be performed a number of ways. One would be to take the maximum horse power derivative engine of that series and run 1000 hours at full throttle, maximum load at the maximum rated engine speed and see if the engineers got it right. Do this to a number of production samples and if all is successful they are ready for release. Like most manufactures this would be just one of the durability tests performed, or something very similar. Given this above example the same company would not need to test their lower hp models of identical mechanical specification for durability, as they have much lower outputs than the original test engine.
So the next question I hear is what durability testing has Nizpro performed on their 332hp tune.
From our perspective we have done a similar version of testing as the above example but we have done this using a 450 Supercharged version of the same engine. Using the same engineering reasoning , if the same power unit can survive a durability test at 450 hp then the likely hood of a mechanical rotating assemble failure at 335 hp would be very very low and not to mention odd. While saying that we have also tested the 332 NA tune very well separately.
The exact same principle can be carried over the rest of the outboards components including the lower unit. The lower unit gets many mentions regarding how quickly they are going to explode after we install a supercharger to the engine on many forums and social media pages. However that has simply not been our experience. We have actually seen no lower unit failures caused by the add power being added to the engines via Supercharging. All lower units and engines wear out over time, that time can be influenced by servicing or lack thereof, but it terms of failure from increased power we have seen zero. Not a single broken gear or prop shaft. In our own testing running power levels well beyond 500 hp we still have never seen a failure of a standard Yamaha lower unit.
I would also like to touch on Brian’s point regarding costs of The Supercharger system and some of its benefits.
The Supercharger system has a broad application base, from very high speed bass boats to large centre consul boats. The added upgrades that Brian mentioned can certain be true in the case of a 22 Foot bass boat that with the standard 250 SHO engine is already running 85 mph. Adding the Supercharger system will have this same boat in the low 100 mph bracket. Yes this boat for handling purposes needs added modifications, better steering, lower unit nose cone and so on. Anyone aiming for maximum speed is always going to want to test and purchase the fastest prop also. But this is a little like hotting up your car’s engine and then fitting better brakes, wheels and tyres, very sensible but it’s just the cost of wanting to go fast.
On the other hand taking a 50 mph Centre consul boat owner who wants to increase his cruise speed by 8 to 10 MPH while still only wanting to sit on 4000 rpm so his economy is still good and not wanting to rev the hell out of his engine for hours at a time, the installation of the supercharger can be done with no other modifications or upgrades other than a prop change, we all except this is standard procedure when wanting the best performance for an individual application. We have also had installs where the standard engines have been prop’s to 5400 rpm, adding the supercharger allowed 6400 rpm and no prop change was require.
So Brian’s point is very valid in as far as the cost consideration is on a case by case application.
Now for the warranty question. I have a very different opinion regarding warranty than many, not all but many.
Firstly for customers wanting to take their 200 or 225 SHO engines up to a standard Yamaha 250 SHO power rating yes we can simple load a standard 250 HP file into your ECU. At this point all the talk about reliability and so on goes out the window, you now have a standard Yamaha 250 hp calibration., its not aftermarket if factory Yamaha. The same goes for the Offshore 225 and 250 and getting them to 300. We of course offer the 332 hp tune as our standard upgrade with a few rpm limiter options.
My comment with warranty is this, people often say I will wait until my warranty runs out, then I will modify my engine, if it then has an issue I will pay for it. This makes no sense to me personally. If you are willing to pay for a problem after the engine runs out of warranty then what really is the difference if you have a problem with a modified engine while it’s in warranty, you’re still going to be paying if an issue arises. But your engine is now 3 years older
Ok you’re losing the built in cost that you paid for your warranty at the time of purchase, banking on whatever goes wrong will be fully covered. On the flip side you’re going to drive around for 3 years knowing that the engine you have is capable of so much more. People are so much more patient than me!!
If you engines are for commercial purposes and you are changing them every 12 month so they are always covered then fine I get it. But if you are generally serious about modifying when the warranty runs out, then when that day comes you have excepted you’re on your own, at that point life’s short modify now and have some fun.
Thanks for having me, hope I’ve helped clear up some of your questions.