New Yammy

[150aintenuff]

The rating is 200. (G3 HP200 DC).

Which 200 are you talking about Nick?
And please explain 300ECM and which xs.
I'm a dummy

OK ... I would get the Yahama for several reasons then BECAUSE

1. G3 is Pre Rigged with Yahama
2. 200, 250, 300 Are Internally the same as far as rotational assemblies and share a common block design. differences MAY include different injectors, port sizing and Computer programing. SO with that said replacing the 200 hp ECM (electronic controll module(computer)) with one out of a 300 is like adding a chip to your vehicle.. Gains will be seen as fuel injected determines HP as much as engine design. figure about around 25% gain .ROUGHLY may be more may be less.
3. That hull is FAIRLY heavy in the sence that its running surface is pretty long and flat=DRAG so the Torque of the 3.3 will definatly be a + Also with the G3 hull the weight will help to somewat offset the longer running surface especially since you arent running the large setbacks that Bullets and other high end Bass boats run.
4 Talk to your dealer they MAY be able to rig the 300 BECAUSE it is the same weight of the 200.. MOST hulls are rated according to the WEIGHT placed on the transom and the forces of the speed of hull on the water in user average conditions. so if weight being equal it would be SAFE to rig the 300 because it is of same weight as the rated 200HP of same line.

The Mercury XS is lighter and a higher reving but doesnt have the warranty of the yamaha and may in the long run be more expensive because the boat will need to be totally re rigged to work with the XS It is also pretuned for the most" possible" power Merc is willing to let that motor have so upgrading it may or maynot be possible... it also may not have the necessary longevity that the " fishin" motor will have because it is a High Perf product and if you want 15+ years out of that boat go with the one that has the longer waranty..

that is just my 2 Cents worth and I am a black motor fan BUT that is changing slowly because of consumer products like the yamaha 300 and other modles from Erude(250 ho) and even some honda lines(20hp).
hope that clears up the mess for ya

BTW if the hull is over 20'1" in length those HP ratings are a GUIDLINE not setin stone. the USCG doesnot rate any hulls over 20'1" and if the manufacture places a rating it is voluntary because the manufacture tested that hull for level flotation using that size of OB.

[VectorPat]

The VZ300 is a different block than the VZ200 (Different Porting) The 300 ecu is not going to make a 200 into a 300 it would probably make it run like crap, but for the $983.00 it costs I am sure someone would gladly sell you one.
I really doubt your are going to find a dealer that is going to rig a 300 on that hull. Too much liability and probably wouldnt find insurance.

[150aintenuff]

vector I said that... the blocks are of same design withparameters... yahama uses an O2 sensor so the aditional timing curve and fuel curve will add some power, not 100 hp But it will add some. I have seen it done many times here on jet pump driving OB here in the NW they go from 225 hp in prop form to160 in jet form they add a 250 ECM to recover a few HP(up to 175 in jet form)(240 in prop) that is lost in the Jet conversion. They run fine and have 0 problems as far as running because of the sensors that optimise the fuel mixture to still be clean acording to the computer.. the dealer may not beable to rig the hull but they can atleast talk to the Manufacture of the hull and inquire as to why a 3.3 L 200 can be riged but not the same engine in higher HP form... Im not that familiar with that hull so it may be under 20" long so the USCG may have athority in the HP ratings. Insurance may be aproblem anyway regardless of 200 or 300 hp.. most companies are setting speed limmits these days and most bass hulls exceed the insurance guidlines... I know for a fact progressive scwabbles at over 35-50 MPH. even with a 200 that hull will run 60.

[cgp]

I understand what your both saying.Makes sense.I'd rather have the Yah.How much does your allison weigh (dry)?I think that 20'G3 is 14oo something.
By the way ,thanks for your info.
cgp
o, How about longivity on that 200sx?

re: DI 200's

For a heavy boat the 3.3L 200's would be my choice
For a lighter boat like my Allison I'd go for the Mercury 200XS

200XS 2.5L 6000-6500 rpm 1.87 gears, 434 lb
Rude 200 HO 3.3L 5500-6000 rpm 1.86 gears, 517 lb
Yamaha 2.6L HPDI VMax 200 2.6L 4500-5500, 1.86 gears, 475 lb
Yamaha 3.3L HPDI VZ200 3.3L, 4500-5500, 1.81 gears, 529 lb

all but the VZ200 data from manufacturer claims
VZ200 from Feb Bass & Walleye boat
They turned their test engine to 5800 rpm
B&W state that the added displacement plus a new lower unit = 3-4 more mph

Only the 200XS requires premium fuel.

Plan B = 200 Carb motors = Merc only choice

Merc 200 2.5L, 5000-5600 rpm, 1.87 gears, 406 lb


Some time this year B&W are doing a 200 comparison test.

[150aintenuff]

I personally dont have an allison so I couldnt tell ya but there is alot of people that do here maybe they can give you an answer. I also dont have an OPTI but I would assume the longevity would be in the range of 10-12 years if well kept up well and the yahama should last atleast 15 years that is assuming 2-4 times their warranty period.
but as we all know there is no guarantee of product life.

[VectorPat]

The 2.6 HPDI has an O2 sensor but it is only used during Idle speeds and is out of the loop after that then the ECU map takes over. The 3.3 has no O2 sensor at all. Changing ECUs will not make either HPDI run better. The EFIs(OX66) are the only motors that use the O2 sensor through the RPM range. I have never tried swapping ECUs around on them. I know that the some of the OX66 150 share the same ECU as some of the 200s though.

[Yamaha 225]

If I do not remember wrong, there are no chip in those ECUs. You have to swap the complete ECU. I bet that cost approx 3000-4000 dollar.... I would go for the Vmax 250 HPDI or if a 300 version is possible, this would be the best engine. Or Merc 250 XS is a good choise. Now they have made them compatible with latham style steering cylinders.

Good Luck! Post the results!!!

[150aintenuff]

you are correct in the ECU swap... but if my memory serves the ECU complete is around 1000-1500.. but he is limmited to 200 hp on spec plate of boat and to go bigger would require the dealer to break the law OR he would have to buy it in box and rig it himself which could cause warranty issues...