Do you need a Blow Off Valve for your Supercharged PWC?

Рет қаралды 12,335

Күн бұрын

It seems like there are a lot of people that feel like you should get a blow off valve (BOV) if you have a supercharged PWC. If that is that case, then why aren't they built with one already installed. In this video, we take a look at BOV's, what they do and whether or not you really need one.

Пікірлер: 64

@watercraftjournal 2 жыл бұрын

Great video, but there's some key points that were missed: 1. 300 and 310HP Kawasaki engines came/come with a BOV because at peak RPM they generate 16.8psi. The maximum boost generated by a Sea-Doo 300 ACE is 8.8psi. The SVHO is 8psi. These are VERY safe boost levels even when pinned at 7700rpm and dropping to idle. 2. Centrifugal superchargers do not generation positive atmosphere until late in the engine's torque curve. 4,400-to-4,600rpm is when boost gauges begin to register usable psi and deliver extra fuel. 3. When you release the throttle trigger it closes the throttle blades...slowing the engine RPM down, so the supercharger is no longer generating boost at any sort of excessive levels. 4. Unspent/unused boost does not cause (in stock psi PWC) supercharger clutch slippage. Erratic throttle control does. The slippage in centrifugal superchargers is/was originally "baked in" to the design to protect the SC drive. Better throttle management software has made it so OE superchargers require less slippage - but all healthy OE superchargers have slippage for this purpose. 5. Even major aftermarket parts vendors have noted that ONLY watercraft generating MORE than stock OE psi levels require an aftermarket BOV. And no, an ECU does NOT increase psi levels enough to necessitate one. 6. The OE's allow the intercooler and tubing to absorb the unspent psi until the throttle reopens, permitting the remaining latent psi to pass in. Owners of previous 255 and 260 Sea-Doos would feel this surge regularly. 7. Latent/stored psi degenerates rather quickly (3rd law of thermodynamics). This positive atmosphere also does not experience a reversion effect (traveling back up), but expands the intake tubes and contracts as it depletes. (Again, speaking for low boost/stock OE psi applications.) Again, great work! I love your channel. Keep it up.

@TheShipsLogg 2 жыл бұрын

Thank you and thanks for the additional information!

@kkutube1972 Жыл бұрын

Thanks

@kkutube1972 Жыл бұрын

@@TheShipsLogg Thanks.

@t.j.goldwater7139 Күн бұрын

Hi there , I have built a mini jet boat with the svho engine. Bone stock, only ribbon delete. With the S/C in front of the engine, I have the air intake between the seats. When I let of the throttle I clearly hear the thuthutu noise. Isn’t this air blowing back through the S/C?

@2SHARP4UIQ150 2 жыл бұрын

Great video. Basic explanation of what a Blowoff is.

@jajcozucchini5438 2 жыл бұрын

Thank you for the video, It made me understand why do I need 3rd clutch already on my 169 HR SVHO Great educational video ,

@TheShipsLogg 2 жыл бұрын

Thanks. I'm glad it helped.

@gerardotorres9963 2 жыл бұрын

Excellent video very well done you explain everything I have 2021 FX SVHO I am not aggressive driver but sometimes I really like to go fast that’s why I bought that machine I put the blow off valve from Riva racing just to be protected because let’s face it we spent almost $20,000 And on my case I am not a reach guy

@TheShipsLogg 2 жыл бұрын

Thanks Gerardo!! One thing that the FX SVHO does really well, is go fast!! Happy Riding!

@silverdollar6548 2 жыл бұрын

I also capt. Frank am not an aggressive rider but will occasionally enjoy the need for speed, with that said, I don’t feel I need this valve installation. Though I do respect the aggressive style I tend not to creat a days work and chance blowing my back out. As always Capt. Frank, excellent vid and thanks once again.

@TheShipsLogg 2 жыл бұрын

Sounds like you and I are on the same page!!

@MrKevcola11 Жыл бұрын

I really enjoyed this video, I’ve come across your content b4 & yes I’m an aggressive rider who blew his clutch 😂

@TheShipsLogg Жыл бұрын

Thanks for watching. I bet that new clutch was worth it though, wasn't it? 🤣

@seadogg404 2 жыл бұрын

Well explained . I need one

@TheShipsLogg 2 жыл бұрын

Yes you do!! I've seen you ride! 😂

@spartacane5904 2 жыл бұрын

Thanks for the info

@TheShipsLogg 2 жыл бұрын

You are welcome!!

@antoniosampedro2804 Жыл бұрын

I don't have one yet just took my permit to be legal in NJ, but I love your videos and you sir are a great teacher.

@TheShipsLogg Жыл бұрын

Thank you! Hopefully you can get some good riding in up there before the weather gets cool.

@scottmurray2532 Жыл бұрын

Thank u for this video, rxpx owner

@TheShipsLogg Жыл бұрын

You are welcome!!!

@teamoutkastrcdragracingrev2933 Жыл бұрын

I’ve got a 21 RXP-X 300 w/ catch can, 90 velocity stack and scom. I do run wide open but never just let off, I just ease out of it until it’s slowed down enough to let off. My wife has a Spark so I mostly just cruise around at her speeds anyway. Trying to get her to trade it in for a bigger one but she’s small and scared of the big one lol

@TheShipsLogg Жыл бұрын

Smart way to ride. Let your wife know that a bigger machine will be a smoother ride when the water gets rough. Maybe that will do the trick! 😉

@CrochetNewsNetwork 2 жыл бұрын

Man I’m learning more from your channel than any other! Well done sir. I ride pretty much like you. However I’m not typically mechanically or maintenance inclined , but your videos now give me confidence that I can properly take care of basic maintenance. You as well give me a knowledge base in which I can intelligently speak to dealer, repair shop, and know what accessories I might need. I’m still agonizing over a 2022 Yammy FX SVHO limited and the 2022 Seedoo GTX 300 Limited. Although the Kawasaki has made wonderful improvements for 2022 I’m just not that keen on the style. It looks too busy to me. I wish I could ascertain what hull and seats of these three jet skis has the most comfort. Dealers hardly have anything in stock let alone a test drive. Any advise fro you would be enormously appreciated

@TheShipsLogg 2 жыл бұрын

As it turns out, I was just having a conversation with. A PWC mechanic yesterday. We were talking about the differences between Yamaha and Sea Doo. We both agreed that Yamaha is a more reliable machine but Sea Doo is more innovative. They do come up with some cool features before anyone else does. My Yammy is very comfortable for me but I know that a lot of people rave about the comfort of their Sea Doo. Hope this helps and I'm glad my videos are helping you.

@CrochetNewsNetwork 2 жыл бұрын

@@TheShipsLogg - thank you sir for your reply. Your advise is greatly appreciated. What I appreciate is your unbiased fact based information. I will probably go with the Sea Doo GTX 300 Limited as I live up in the Pacific Northwest . Meaning my summers are short, no salt water, and a few local lakes. I agree with you the Yammys are more reliable, but I’m crossing my fingers I won’t have many problems with SEA DOO due to the fact I won’t be riding too hard. We do have a couple large lakes that get quite rough so I’m hoping for a low and wide hull to cut through along with a comfortable seat. At my age I have some back pain and can’t do a whole lot of bouncing around at 45 to 59 mph However when the water is smooth, I’m a full throttle kind of guy:-)

@TheShipsLogg 2 жыл бұрын

@@CrochetNewsNetwork Awesome! Good luck with your new machine!!

@Maxrotor1 2 жыл бұрын

Thanks captain. I will have to consider this for my new 2022 FX SVHO Limited.

@MarkCamo69 Жыл бұрын

I have the same model, lets face it if you are out with mates everyone races, and i will ride it erratically on throttle most likely as well, most of us do, so that's why i put a Fizzle hose with Turbosmart BOV to fit in with stock airbox, i also use a full Riva (k&N) air filter for stock airbox, and i modified the airbox as well, not sure how to post pics here for you to see what i did

@jasonmekush5280 2 жыл бұрын

Yeah im w wcj here no blow off valve needed unless u go to a big wheel motor.

@michaellindon5688 2 жыл бұрын

Interesting

@jayppop3333 Жыл бұрын

Wonder if you can feather the throttle to help release pressure

@TheShipsLogg Жыл бұрын

That does help as it prevents "slamming the door" on the built up pressure.

@scottlovesplayingbass3495 2 жыл бұрын

I agree and I have a GP 1800 supercharge but I’m not gonna drive like that. But I did add a breather upgrade that helps the motor.

@BaronTeaParty Жыл бұрын

did you add a oil catchcan with the breather?

@Mroswaldo16 Жыл бұрын

Jumping waves is only.for personal injuries. When jumping waves just let go of throttle, so at the end of the day, yes you need one! Not even 7 hours on my 22 fx & first thing i got was a blow off valve! Then, ribbon delete kit.

@lynncampbell8503 2 жыл бұрын

Will this void the warranty. 22 GP 1800 SVHO

@TheShipsLogg 2 жыл бұрын

It should not as long as the job is done right. Most people probably don't need one though.

@kupar2095 2 ай бұрын

So if I understand correctly all that gasoline air mixture goes into engine compartment?

@TheShipsLogg 2 ай бұрын

No gasoline. Just the compressed air. The blowoff valve releases any unused compressed air before it reaches the combustion chamber.

@juanjortega8558 2 жыл бұрын

what about seadoo gtr 230 can be recommended for a driver that have both agressive and cruise ?

@TheShipsLogg 2 жыл бұрын

If you have not made any modifications to the machine to increase the power, you should be good. If you have made modifications, you might need to consider it.

@juanjortega8558 2 жыл бұрын

@@TheShipsLogg thanks 👍 great video btw

@irvingonzalez9576 2 ай бұрын

What PSI should the valve be set to ?

@TheShipsLogg 2 ай бұрын

That depends on the system that it is installed on. Different superchargers are designed for different boost values. Setting the value too low pretty much nukes your supercharger while setting it to high defeats the purpose of installing it.

@schoolsout2069 2 жыл бұрын

I ride like you for the time being. Have a 2021 FXSVHO with 11 hours (need to do oil change) and extended warranty. Do these addons void warranty? Obviously, tune and other stuff would, but wondering if this is more of a preventative type thing Yamaha wouldn't have an issue with.

@TheShipsLogg 2 жыл бұрын

It's always best to check with your dealer but I don't think it would void the warranty. As you said, it's more of a preventative measure. Of course, it may give your dealer a hint as to how you operate your ski. 😂

@Jay_Hall 2 жыл бұрын

It would be very wise to leave all stock for warranty purpose,,especially for the extended warranty. :)

@TheShipsLogg 2 жыл бұрын

@@Jay_Hall agree

@Mroswaldo16 Жыл бұрын

Bov doesnt void warranty. Just keep the stock boot, to swap if you dont feel comfortable

@danav3387 2 жыл бұрын

I consider myself a pretty aggressive rider. I have a bone stock 09 FZR with 350+ hrs and 0 issues with my supercharger. My midshat bearing is bad but no other issues.

@TheShipsLogg 2 жыл бұрын

That is awesome. Not surprised that you have a Yammy. Yamaha seems to design their machines so they are not overstressed, even if you are an aggressive rider. This helps to ensure that you have many hours of trouble free riding. 😁

@donaldbell9669 Жыл бұрын

I am one of them aggressive riders how much does one of these cost?

@TheShipsLogg Жыл бұрын

There are different brands and it also depends on your ski but I would say that you should be able to get one for under $500

@Dr_Flankensteinn 2 жыл бұрын

Great Video Capt. Frank - can you do one on a CATCH CAN? :)

@TheShipsLogg 2 жыл бұрын

You are reading my mind Jeff. I have already been thinking about getting one to test. Stay tuned!

@Dr_Flankensteinn 2 жыл бұрын

@@TheShipsLogg I just had one installed - as a recommendation to keep the intercooler from getting oil buildup/residue

@TheShipsLogg 2 жыл бұрын

@@Dr_Flankensteinn That is what I have heard as well.

@paulpuglia8480 Жыл бұрын

On the same note of the blow off valve, the oil catch can is it necessary to get an oil catch can on and on a natural aspirated engine???

@TheShipsLogg Жыл бұрын

Good question. I know plenty of people who swear by them and say they make a difference. I personally have not put one on my supercharged ski and I am not using any oil at all. It seems to me that it may only be necessary if you have modded your machine. I am thinking about adding one as a test just to see if it actually makes a difference on a stock machine. Stay tuned.