SX 195 Performance Engine Mods

[SimonsJ]

I would suggest checking your impeller for any damage and its clearance between the impeller sleeve along with sealing your intake tunnel. When my impeller sleeve and impeller was out of spec it performed similar to as you described.

When I pulled out the drive and disassembled the jet, the Impeller and sleeve looked brand new... perfect.
The previous owner clearly had issues because the tunnel has waaay too much sealant on every possible seam. I can't see any way that my tunnel has the usual leaks.

Where else can the air be getting in there?
Is it possible that air can get into the tunnel at the plug? I have water sitting on top of it whenever I check it, but I haven't tried looking at it underway (holding the safety switch).
Is it just a high altitude issue?

I have the 12/18 Twin Impeller and will try to get that installed... If I can get the stock impeller off the drive shaft!

 

[SimonsJ]

General consensus is that unless your boat is heavily modified you will see the best performance with the stock impeller.

At sea level... definitely not the best impeller above 3,000' ASL

 

[blacksapphirez]

anyone tried these?

MACSBOOST High Performance Air Intake Yamaha SHO/SVHO Supercharged Waverunner | eBay

Designed in Race City USA by MACSBOOST Incorporated. Integrated Velocity Stack design increases flow, significantly more flow than no intake at all. Equivalent of a 6" intake with a zero length hose.

www.ebay.com

Supercharger IMPELLER 19.6PSI For Yamaha 1.8T FX / Cruiser SVHO FZR / FZ | eBay

Find many great new & used options and get the best deals for Supercharger IMPELLER 19.6PSI For Yamaha 1.8T FX / Cruiser SVHO FZR / FZ at the best online prices at eBay! Free shipping for many products!

www.ebay.com

GreenHulk PWC Performance Store - FIZZLE 500 Intercooler for Yamaha Skis with 35mm non-brand name BOV

Includes off-brand 50mm or 35mm blow off valve (your choice)Typical top speed gains of 2+ MPH over OEM Yamaha SHO or SVHO intercoolerTypical peak RPM gains 200+, acceleration and throttle responseKit Contents: The intercooler with blow-off valve flange, blow off valve, full piping kit, mounting...

www.4-tecperformance.com

https://worxracingusa.com/products/yamaha-2020-svho-single-fitting-high-flow-pump-strainer

 

[blacksapphirez]

When I pulled out the drive and disassembled the jet, the Impeller and sleeve looked brand new... perfect.
The previous owner clearly had issues because the tunnel has waaay too much sealant on every possible seam. I can't see any way that my tunnel has the usual leaks.

Where else can the air be getting in there?
Is it possible that air can get into the tunnel at the plug? I have water sitting on top of it whenever I check it, but I haven't tried looking at it underway (holding the safety switch).
Is it just a high altitude issue?

I have the 12/18 Twin Impeller and will try to get that installed... If I can get the stock impeller off the drive shaft!

I have L13 cone with no spacers. MUCH better than stock cone but still a little bit of caviatation.

 

[Extremneon]

This is a great thread, stumbled upon it when looking for jet boats running the Fizzle Y1000 Intercoolers.

I have 2021 SX195 and looking at making a few upgrades in the future to make the boat run better and of course a bit faster.

 

[Scat Adams]

Bump! What BOV are you guys running on stock 195s?