SX 195 Performance Engine Mods

[swatski]

That’s a great question... I don’t want to lead you in the wrong direction and I’m not sure if by changing it to a lower pitched impeller, but keeping the horse power the same will raise the RPMs.. @swatski @SamCF What do you guys think?? I was under the impression that when you making more power, the 13/18 is better suited at transferring the power into thrust and thus increasing the hookup and top end.

When it comes to the last few hundred RPM on top and few mph, the nominal impeller pitch numbers mean nothing. What I mean is - the pitch needs to be tweaked manually, and the OEM impellers are the best for that. Even is you send it out to Impros they will send it back for you to test and it wil be an iterative process. Making small changes to the trailing edge (pitch) is fairly easy and really to only way to get close to your target RPM.

My first hand experience is solely with N/A 1.8, and the OEM impellers absolutely rule in the boats. I have tried literally every type and brand of impeller including custom pitched RIVA branded Solas and Skats from Jerry Gaddis, those work great in jet skis but the results do not translate to boats. I think the loading is just totally different given weight and intake considerations.

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[swatski]

The big difference with supercharged 192/195 is by increasing the top/max RPM (for example by slightly depitching trailing edge on the impeller) one gets more boost, so pushing the rev limit (for example to 8,350 RPM) makes a lot of sense as it can give real power gains.
As opposed to N/A where higher RPM does not give much power gain, and it is nearly impossible to get more speed on top with an ECU reflash as the timing is usually already maxed out at WOT.

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[DavisAR195]

So after going through this thread I decided to put my factory cone back on to see if I could hit 7,800 RPM’s. Over the winter I did the ribbon delete, CAI, breather and added the L13 cone but never tested the boat with the factory cone. With the cone and all 3 spacers I consistently run 7,550 to 7,650 RPM’s with a top speed of 48 to 52 depending on my load.

So I put the factory cone on in hopes of picking some more RPM’s and few more MPH. What found is my consistently tops out at 7,650 to 7,700 RPM’s and 52.8 MPH GPS was the top speed with the factory cone. (1/2 tank of gas and 1 passenger 210lbs) So it would appears that the 1.8 SVHO are governed at 7,700 RPM.

With the L13 and all 3 spacers installed I thought I had lost RPM’s but the boat definitely has more power to give it’s just bumping up against the max RPM’s.

 

[Smitty78]

So after going through this thread I decided to put my factory cone back on to see if I could hit 7,800 RPM’s. Over the winter I did the ribbon delete, CAI, breather and added the L13 cone but never tested the boat with the factory cone. With the cone and all 3 spacers I consistently run 7,550 to 7,650 RPM’s with a top speed of 48 to 52 depending on my load.

So I put the factory cone on in hopes of picking some more RPM’s and few more MPH. What found is my consistently tops out at 7,650 to 7,700 RPM’s and 52.8 MPH GPS was the top speed with the factory cone. (1/2 tank of gas and 1 passenger 210lbs) So it would appears that the 1.8 SVHO are governed at 7,700 RPM.

With the L13 and all 3 spacers installed I thought I had lost RPM’s but the boat definitely has more power to give it’s just bumping up against the max RPM’s.

Doing a ribbon delete and CAI Intake is going to only give you negligible power gains on a forced induction engine like your SVHO. On on a NA engine it will be more noticeable especially when at a higher altitude. 52.8 Mph is right where you should be for your AR-195.

 

[jEt_jAk]

Installed the lucky 13 cone. Wow what a difference. No cavitation 0 to no top speed loss.

 

[Smitty78]

Installed the lucky 13 cone. Wow what a difference. No cavitation 0 to no top speed loss.
View attachment 103757
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Nice Job!! ?? I noticed one thing from your photo... Next time you have to take your jet pump off to do any service, you can leave the articulating keel on and still remove the nozzle end and jet pump. I learned this the second time I had to take it apart.. It’s one less thing to take off.

 

[jEt_jAk]

The problem is I have the lateral thrusters which completely block the two bolts on the bottom of the pump. I had to remove the entire lateral thrustor assembly to get to it. Was quite a job lol.

 

[Smitty78]

The problem is I have the lateral thrusters which completely block the two bolts on the bottom of the pump. I had to remove the entire lateral thrustor assembly to get to it. Was quite a job lol.

I have the lateral thruster from Jet boat pilot too. If you take out the two hex bolts on either side for the support brackets of the lateral thruster first. Then take the two top jet pump bolts out. After that you can use a ratcheting/open ended wrench and you can squeeze between the two and loosen half on the one side then half on the other. Then go back to the first side and loosen that bolt all the way out and then finish on the other side. When you’re putting them back together you’ll use a small flat head screwdriver to put pressure on the bolt as you’re tightening it, to thread it back in.

I’ve done it this way a few times now and it works like a champ!!

 

[jEt_jAk]

Good to know! Couldn’t fit my ratchet in there will keep in mind for next time! I tried an adjustable wrench and couldn’t fit but I suppose an open ended non adjustable may. I hate taking off that keel such a pain to get that center bolt and snap ring on there.

 

[DavisAR195]

I have you all beat, when I originally installed the L13 I pulled the nozzle. I have learned with a long extension, I changed out the cone with leaving everything intact and squeezing my hand through the nozzle.

 

[Jonnyspeed]

Really tempted to upgrade this Winter. Question on the tune... which would I want if I'm planning to stay with the stock impeller, L13, CAI, Intercooler?

 

[jEt_jAk]

I did CAI and really not much of a noticeable difference at least with the ribbon still in there. I would say L13.

 

[Jonnyspeed]

Has anyone replaced their pump with the Solas Stainless Steel Pump, Yamaha SVHO/6ET, 160mm/12-Vane? how much difference it would make on a modified setup?

 

[DavisAR195]

Has anyone replaced their pump with the Solas Stainless Steel Pump, Yamaha SVHO/6ET, 160mm/12-Vane? how much difference it would make on a modified setup?

I’m not aware of anyone as most people put their money to better use on a L13, upgrading the intercooler or tune.

 

[Smitty78]

Really tempted to upgrade this Winter. Question on the tune... which would I want if I'm planning to stay with the stock impeller, L13, CAI, Intercooler?

The Riva Maptuner X stage 1 tune will work well for the setup you’ve described.

 

[Smitty78]

Has anyone replaced their pump with the Solas Stainless Steel Pump, Yamaha SVHO/6ET, 160mm/12-Vane? how much difference it would make on a modified setup?

If you have 155 mm pump and going to the 160mm pump, it will make a difference. If you already have a 160mm pump there is no difference.

 

[Jonnyspeed]

Ordered my L13 since they had 20% off at 4tech. So it begins... Intercooler, MapTuner, Solas next? Probably. Although, I think I'm going to have my dealer install the new impeller at the same time I have it serviced in the Spring. I've read that keeping the RPM under 8600 should be ok, but are there any reports of engine issues with the increased RPMs over stock? Planning on the 8500 RPM tune, estimating actual RPM of 8200-8300 range. Just want to have some piece of mind that I'm not going to blow up my family's summer fun.

 

[Smitty78]

If you use the Riva Stage 2 tune you’ll be right at 8300 rpm with those mods. Your gonna love it!!!

 

[Djkinn13]

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[Smitty78]

So, I got a little crazy and I’m completing the last mod to finish up the stage 3 build, that I doing to my SX195.

Here’s a list of the mods that I have completed so far...

*Jet boat Pilot Lateral Thruster
*Wet Wolf Yam-5 Adjust a Thrust
*Solas Concord YV-CD-13/18 Impeller
*K&N Cold Air Intake
*Fizzle Factory Y-1000 Intercooler
*HKS SQV4 Blow off valve
*RIVA Racing MaptunerX Stage 3 Tune
*Worx High Flow Water Strainer
*Engine-Tech 17 PSI Boost Wheel
*Riva Racing 1000cc Fuel Injectors
*PLX Monitor with Bosch Wideband O2
*R&D O2 Sensor Housing
*AMSOIL 10w40 Marine Synthetic Oil
*Resonator Delete w/Custom KCS Free Flow Exhaust

Jesus at Riva racing was able to build a custom tune and we got everything dialed in before the end of last season. Currently it will do 60 mph @ 8550 rpm with a full tank of fuel, 3 adults, and gear.

The only upgrade I’m completing right now is to remove the jet pump and switch to a SOLAS Concord YV-CD-14/21 impeller. I am currently running a SOLAS Concord YV-CD-13/18. After speaking with the guys at Impros, I decided it was a good idea because the boat is making, so much more power than stock motor, With the higher pitched impeller of 14/21, it will lower the rpms to about 8350 at WOT, but will increase the top speed to about 63 mph, with a normal load.

I’ll let everyone know how it goes, once I’m done....

Based upon what I’ve seen so far in regard to adding power to these boats; is that eventually your drag limited by the design of the hull!!