Jet pump "blueprinting" (how it's done) - by WFO Performance

[swatski]

I love how my boat runs now -- probably similar to or better than a new 195! When I started the upgrade project, I didn't know Yamaha was going to upgrade the 2017s. Had I known, I would have considered a trade. But, I don't think the math would add up very well. Something like 20k trade in for my boat put towards 40k in price, fees, taxes for a 2017. So, 20k difference vs 6 k for the work I had done.

On another note, I just got home from the Houston Boat Show, and they are offering some seriously good deals on 2016 models for anyone looking for a discount!

The top speed is what everyone is asking and talking about, but in REALITY it means almost nothing, at least not much when it comes to water sports and cruising. It is the low end and the hookup with no cavitation that makes for the utility and the exhilarating experience in these boats. Certainly, sounds like WFO guys (@WFO Performance) know how go about it!

Along the same lines, the choice of R&D R3 reflash is probably a brilliant move. It has been unanimously considered an "extremely good tune" in the jet ski world. I experimented with Vtech tunes for a while in my 190, mostly because of the flexibility of the Maptuner where you can go back and forth between the tunes and the backup. I had a great experience and, surprisingly, not because of the top speed gains (which were mediocre with the N/A engine) but because of the low and midrange power gains. I am toying with the idea or doing it again in the new twin.

Frankly, the biggest improvement to boating fun gained with the tune, at least in my case, came from the smoothing out of the throttle response. I wonder @erj1452002 if you have noticed any differences in that regard. In my old 190, and the new 240, throttle response is very sloppy (awful) -- NOT due to any slack in cable but the ECU mapping. I could tell that for a fact as was switching between reflash and backup ECU programs with my Maptuner, without touching or changing anything else.

(I think that throttle response is much improved in E-series boats, with fly-by-wire technology, but they have their own quirks kept me from buying into it, at least for now. )

That improved throttle response is a bit difficult to show without actually piloting the boat. Here are some short clips of video trying to do give an example.
The first clip is in stock mode. Note how much play there is in the throttle movement, out of synch with RPMs, especially in the middle of the range. Throttle cable is tight, so this is all about ECU mapping.

This second clip is in Stage 1 reflash mode.
(I don't recall which particular program I was using in the video, but Vtech has various versions with vastly different throttle response from laid back to aggressive -- this one was one of the "agr" programs I think)

Nothing changed but the ECU reflash. Note how much more precise the throttle control is, especially in the midrange. The RPM response is immediate and tightly tethered to throttle movement - no slack, no "play".

Again, those differences are difficult to measure or illustrate, but the feeling is not subtle, and it is GREAT.
It is also very helpful for tight speed control in wakeboarding ranges, it is simply much easier to control the speed and acceleration without any slack in response.

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[erj1452002]

Swatski, I think I understand your question, but since this is the only boat I have driven in 30 years, I don't have anything to compare it to. My level of throttle awareness right now is limited to forward = faster and backward = slower. lol I have really never had the thought of "jeez, I wish that were smoother in that range" or anything like that. I did notice a little dead range up near max throttle before the upgrade, and the dead range seems to be a little less now after the upgrade. Next time I go out, I'll focus on the throttle a bit more and get back with you!

 

[swatski]

Swatski, I think I understand your question, but since this is the only boat I have driven in 30 years, I don't have anything to compare it to. My level of throttle awareness right now is limited to forward = faster and backward = slower. lol I have really never had the thought of "jeez, I wish that were smoother in that range" or anything like that. I did notice a little dead range up near max throttle before the upgrade, and the dead range seems to be a little less now after the upgrade. Next time I go out, I'll focus on the throttle a bit more and get back with you!

When I take my boat out next time, I'll shoot a clip or two to illustrate. "Dead range" is a good way to describe it. It really bothers me, I admit. I like it tight, no slack, zero dead range.

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[WFO Performance]

@ISLANDRACING and @WFO Performance would you say that blueprinting the pump on a double jet boat would be beneficial?
I did it very roughly when I first bought the boat, just simply smoothing things out by eye. I don't know if it helped because I replaced some beat impellers at the same time and went from 47 mph to 52. Now I added subs, tower, speakers blah blah blah and I'm back down, lol!
And actually, I never took the "ride plate" off of mine because I started stripping the bolt off on both of them. Any tricks to that? Super stubborn bolts that haven't come off ever since assembly so I don't know if I want to mess with it!

Not so much the actual pump stator sections, but cleaning up and sealing the tunnel, yes

The ride plate bolts go into an aluminum insert in the fiberglass if I remember correctly. You can try to gain access to the top of the inserts and blast with some Penetrating oil first. If they do break unfortunately its a drill and extract or drill and tap situation.

 

[CrankyGypsy]

And actually, I never took the "ride plate" off of mine because I started stripping the bolt off on both of them. Any tricks to that? Super stubborn bolts that haven't come off ever since assembly so I don't know if I want to mess with it!

i'll add to what @WFO Performance said above. i took mine off and they were a tough as this was on a 2005 salt boat. i went at the stubborn ones with the allen on a 3/8" drive via an impact driver a few times. the ones that didn't work on, i tried heating/cooling the bolts with a torch, then i'd give the bolts a go with a breaker bar, and repeat. after a while, some of the heads would round out. that's when i busted out the security/star key on a 3/8" drive - it's bigger than the hole: you have to drive it in with a hammer. trust me, if you line it up right, it will route a path and have a stronger/improved grip (it will look like it was always a star bolt). once i got that in, the breaker bar pulled the gnarly ones out easily. don't forget to order new bolts.

 

[ISLANDRACING]

PWC's would respond better to these mods better than boats for the sole reason that 99.9% of the time the intake of the boat is always underwater. The puropse of "sealing" is to prevent air from being sucked in. If your boat wasnt sealed properly from the factory, or the seal blew out over time, yes it is a good idea to reseal.
Also there are 2 sides to every coin. Some want TOP SPEED and some want HOLESHOT. everyone has there preference and some are willing to sacrifice one for the other. more-so in the PWC side.

 

[4wheeldeal]

Not so much the actual pump stator sections, but cleaning up and sealing the tunnel, yes

The ride plate bolts go into an aluminum insert in the fiberglass if I remember correctly. You can try to gain access to the top of the inserts and blast with some Penetrating oil first. If they do break unfortunately its a drill and extract or drill and tap situation.

Assuming mine new boat is easy to come apart I was thinking about shimming the ride plate just a bit. Have you guys played with that? The nose seems to be in the water all the time. Or a 2 deg pump wedge?

 

[ISLANDRACING]

Assuming mine new boat is easy to come apart I was thinking about shimming the ride plate just a bit. Have you guys played with that? The nose seems to be in the water all the time. Or a 2 deg pump wedge?

Uh oh... tell me Island Racing is going to have to start modding Jetboat rideplates now ...As the originators and known for some of the worlds fastest rideplate mods for PWC, I can tell you there is definately huge gains on PWC when addressing this area. How this translates to boats.... well the principle is the same, but the results I have a feeling will be nowhere close to that of the PWC , due to the length, and weight of the boats. That doesn't mean there could be some gains. When it comes to modding boats you have to do ( and spend ) a LOT to gain a little, just the nature. Some people "kill" for 1/2 mph... lol

 

[4wheeldeal]

Gotcha. I figured with the amount of surface area in the water just a bit of trim would go a long way at 50mph.

 

[ISLANDRACING]

If your interested in the wedge, We have a stocking order going in next week for a bunch

 

[Speedling]

Gotcha. I figured with the amount of surface area in the water just a bit of trim would go a long way at 50mph.

I installed 2 degree wedges in my pumps. Might have gained like 1/2 mph and a little more nose up but by the time you hit 35-40 mph the boat hull overcomes it and puts the nose back down. I like it at the angle for 30 mph on Lake Michigan which can have a rogue wave from time to time and helps keep us dry. We try to keep everyone in the back when it's actually rough water unless the kids go up front to try and get air on the bog waves.

 

[Bruce]

If your interested in the wedge, We have a stocking order going in next week for a bunch

How much are these wedges? Since I have trim tabs to push the bow down it might be interesting to have the bow start at a higher angle.

 

[swatski]

@dan144k is the only person, to my knowledge, running offset steering nozzles. His are downward a couple of degrees, so opposite to what you are trying to do, but the same concept. I believe he has lost 3-4mph which, again, would indicate it may be a reversible trend! Which would be good news, right?

Unless, of course, our boats are engineered with an optimal/perfect angle.

Kind of improbable from Yamaha, as I feel they do not optimize ANYTHING really. But I have failed (miserably) playing with ride plate angles in my 190: improbably I was loosing both speed and handling moving it away from factory angle... IDK.

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[Speedling]

How much are these wedges? Since I have trim tabs to push the bow down it might be interesting to have the bow start at a higher angle.

I bought mine from a guy on greenhulk named Leo i believe. My boat seems to DRIVE more bow heavy than the 230 and 240 series even though less weight overall. With the wedges it compensates slightly but hardly noticable until the bow settles back down at higher speeds.
I can show ya at Bimini @Bruce

 

[ISLANDRACING]

The AQUA SPORT wedges are $85.00. We added then to our site in the jetboat section: http://islandracing.net/yamahajetboats.html
We are a dealer for "LEO's" also, ...but they're more than double the price.

 

[dan144k]

Before I welded and redrilled my nozzles to make them offset downward I looked at the pump wedge idea, however they are only made to offset upwards (from what I have found). I have thought of having a friend at a machine shop make me some custom wedges like I would want.

Ideally I would like to locate a 0 degree or 2 degree nozzle. Which would allow the pump flow to be more linear. Currently when it comes off the impeller it goes up 5 degrees (stock) in the nozzle, then down 2-3 degrees (estimate) when it goes thru the steering portion.

 

[Bruce]

@dan144k, did you find a benefit to modyfing your nozzles?

 

[dan144k]

@Bruce
Less cavitation, and better impeller hookup.
Jet blast or thrust does not rooster tail and spray tubers. now 20' compared to 60' behind boat (guestimate again)
I think it helps surfing, by pushing the jet more under the water.
Pushes the bow down, helps on lake michigan when pushing through waves.
Pops up on plane better.

I have 4 nozzles, 2 are stock and 2 are modified (angled downward) I switch them back and forth once in a while to test and try different things. The biggest difference is the rooster tail.

I need to spend more time testing to verify top speed differences between the steering nozzle changes. And then there also is the question about efficiency and fuel which I have zero information to voice an opinion about.

When the boat is running well enough we try and use it and enjoy it

 

[Bruce]

@dan144k was it the #29 deflector nozzle or the #26 nozzle that you adjusted the angle on?

#29 changed from part number 65B-51313-00-8S to 65B-51313-10-8S between 2007 and 2008 then remained the same until 2014. . I believe the change may have provided around a 2 MPH increase in speed between 2007 and 2008 230 HO models.

 

[swatski]

@dan144k was it the #29 deflector nozzle or the #26 nozzle that you adjusted the angle on?

#29 changed from part number 65B-51313-00-8S to 65B-51313-10-8S between 2007 and 2008 then remained the same until 2014. . I believe the change may have provided around a 2 MPH increase in speed between 2007 and 2008 230 HO models.

View attachment 50891

Oh, I would think definitely the venturi nozzle (#26). The base of it would be ground up to angle it, or one would stick a wedge there (between the nozzle base and the transom plate) to tilt it few degrees.
I have one or 2 of those (venturi nozzles) laying around somewhere -- leftovers from the time when I was tuning the L13 cone set up in my 190 - part of the tuning process involves boring out the venturi opening. One of those I know is 90mm (from the original 85mm) - wouldn't work well in your set up (once you bore it out, it can not be un-bore-ed) but it could be useful to figure out how to grind the base. I'm pretty sure I can find it if anyone wants it - just let me know, pm me an address and I will put it in the mail.

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