Nitrous on a superjet

[wsuwrhr]

What dude???

So you are saying you WANT the couplers to break? So every ride, or every other ride you are going to take the motor out and replace couplers?

Interesting scenario.

Maybe you misunderstood me, what I meant to say was to replace any weak links in your drivetrain, otherwise you will be replacing them.


Brian

seems that in this situation..STOCK couplers would be a way better option....like you said, the nitrous will find the weak link....

since the billet couplers wont break, they will transfer the stress to the shafts and crank...

personally, I'd rather disintrgrate couplers vs. having to fix a high dollar crank..

 

[yamanube]

He is saying there is ALWAYS a weak link, the coupler is the easiest link to replace. If your coupler doesn't break, what will? Shaft? Crank? Prop?

 

[wsuwrhr]

He is saying there is ALWAYS a weak link, the coupler is the easiest link to replace. If your coupler doesn't break, what will? Shaft? Crank? Prop?

No, the idea is to REPLACE the weak links.

 

[Idok]

He is saying there is ALWAYS a weak link, the coupler is the easiest link to replace. If your coupler doesn't break, what will? Shaft? Crank? Prop?

thats exactly what i was thinking....

No, the idea is to REPLACE the weak links.

but there will STILL be a weak link! if its not the couplers then where is it? what will be the next most likely part to fail? there will always be a weak link......you just have to choose where you want it..

or, engineer it so that it lasts a long time..but when it does fail, it'll be catastrophic




at least this is how it plays out in my twisted mind......

 

[Matt_E]

From an engineering point of view: A drivetrain doesn't have to have a weak link. All components can be sized appropriately to handle the power doled out by the engine.
A car doesn't have "meant-to-fail" weak links, either. Everything is designed to work together to handle the power of the engine.
Increase the power, and you need to beef up the components. It doesn't mean that it will fail.

 

[wsuwrhr]

Thank you, I was hoping....well let's just say I wasn't sure, if the conversation was serious or not.

Brian

From an engineering point of view: A drivetrain doesn't have to have a weak link. All components can be sized appropriately to handle the power doled out by the engine.
A car doesn't have "meant-to-fail" weak links, either. Everything is designed to work together to handle the power of the engine.
Increase the power, and you need to beef up the components. It doesn't mean that it will fail.

 

[ATS_Aaron]

will the 20oz or the 40oz fit inside the fire extinguisher case? ya know for those that want to have sleepers :drive:

I am pretty sure the 20oz will fit but you would have to cut the threaded lip off, I think the trick would be to gut the backside of one and put it over the bottle.

ATS_Scott finished fixing the starter wiring. We not have a functional ski with a functional nitrous kit. I hope we will have a chance to hit the lake tomorrow.

Aaron

 

[wsuwrhr]

I am pretty sure the 20oz will fit but you would have to cut the threaded lip off, I think the trick would be to gut the backside of one and put it over the bottle.

ATS_Scott finished fixing the starter wiring. We not have a functional ski with a functional nitrous kit. I hope we will have a chance to hit the lake tomorrow.

Aaron

Too bad I am here in Cal. How hot is it where you are in TX right now? Should I be complaining or happy I am here?

Brian

 

[Ericfox]

I wish I lived close enough to help with this... I should have a crap ski to do this stuff on.. it would be fun to have something to screw around with...

 

[yamanube]

From an engineering point of view: A drivetrain doesn't have to have a weak link. All components can be sized appropriately to handle the power doled out by the engine.
A car doesn't have "meant-to-fail" weak links, either. Everything is designed to work together to handle the power of the engine.
Increase the power, and you need to beef up the components. It doesn't mean that it will fail.

And this is true, in stock form. Put a blower and some street slicks on and you start twisting driveshafts, beef up the shaft and you start breaking axles, beef up the axles...you get the idea. You point is valid if we where talking about a stock ski but you and I both know that something WILL break (or are you saying you have properly engineered your ski so no driveline components could ever fail?) It does mean it WILL fail, just a matter of where and when. He could use a custom coupler, then a stronger driveshaft, maybe a stronger midshaft, etc. but that would be getting away from the point, power on a budget. Are billet couplers specifically engineered to handle the exact torsional load as the driveshaft or are they just designed to fit the threads and be stronger than OEM I highly doubt its the former and if it is the latter then you now have a weak link. Are the splines on the shaft(s) strong enough to hold to the breaking point of the shaft, doesn't seem that way, would you rather replace a stripped driveshaft or a cast aluminum coupler?

 

[orangefinger]

To start playing with Nitrous I would suggest to use a SJ 650 engine due to the fact that all parts like cylinder,crank cases are cheaply avaliable.....:Banane13::haha:

Here is a very interesting link

http://www.nitrous.info/nitrous-historic/index.htm:

 

[kevbo]

How is nitrous going to break anything in the drivetrain?

 

[Matt_E]

And this is true, in stock form. Put a blower and some street slicks on and you start twisting driveshafts, beef up the shaft and you start breaking axles, beef up the axles...you get the idea. You point is valid if we where talking about a stock ski but you and I both know that something WILL break (or are you saying you have properly engineered your ski so no driveline components could ever fail?) It does mean it WILL fail, just a matter of where and when. He could use a custom coupler, then a stronger driveshaft, maybe a stronger midshaft, etc. but that would be getting away from the point, power on a budget. Are billet couplers specifically engineered to handle the exact torsional load as the driveshaft or are they just designed to fit the threads and be stronger than OEM I highly doubt its the former and if it is the latter then you now have a weak link. Are the splines on the shaft(s) strong enough to hold to the breaking point of the shaft, doesn't seem that way, would you rather replace a stripped driveshaft or a cast aluminum coupler?

I think you missed my point.

 

[Idok]

From an engineering point of view: A drivetrain doesn't have to have a weak link. All components can be sized appropriately to handle the power doled out by the engine.
A car doesn't have "meant-to-fail" weak links, either. Everything is designed to work together to handle the power of the engine.
Increase the power, and you need to beef up the components. It doesn't mean that it will fail.

it may not have "meant to fail" links....but most of them do


discounting high dollar german cars like Porsche etc etc......


Take a subaru for example.....a non STi wrx will only handle 300lbs of torque or so on a stock tranny

a CHEAP and easy way to make power in those cars is to swap an STi turbo onto it....and add a manual boost controller (not rec'd).....well, now you have all this extra torque..and with the MBC you can start adding boost like no tomorrow

very soon this WILL cause a transmission failure....and right there, boom...4k to build a tranny that will withstand the engines increased output

but the "cheap" factor just went out the window.....

And this is true, in stock form. Put a blower and some street slicks on and you start twisting driveshafts, beef up the shaft and you start breaking axles, beef up the axles...you get the idea. You point is valid if we where talking about a stock ski but you and I both know that something WILL break (or are you saying you have properly engineered your ski so no driveline components could ever fail?) It does mean it WILL fail, just a matter of where and when. He could use a custom coupler, then a stronger driveshaft, maybe a stronger midshaft, etc. but that would be getting away from the point, power on a budget. Are billet couplers specifically engineered to handle the exact torsional load as the driveshaft or are they just designed to fit the threads and be stronger than OEM I highly doubt its the former and if it is the latter then you now have a weak link. Are the splines on the shaft(s) strong enough to hold to the breaking point of the shaft, doesn't seem that way, would you rather replace a stripped driveshaft or a cast aluminum coupler?

matt he didnt miss your point...he covered it right here

 

[butti]

i dont think driveline parts will be the problem.i REALLY dont think couplers are gonna fly apart from the raw nos power haha.

i think the major problems will be controlling overrev and compression,these are the two factors that will conspire to grenade the engine.the other will be finding the right impeller pitch so the ski will not be a dog when riding normal,yet still perform well on the bottle.

 

[ATS_Aaron]

First ride report

We took the nitrous test ski out to the lake today. The results we mixed. The test ski is a totally stock 650 square nose. It's a total POS.

When we hit the juice on a setup wake or boat wake it cavitated and immediately hit the rev limiter. I got maybe 2 good jumps out of it. The power increase is INSTANT and it is significant. I forgot how low the stock 6M6 rev limiter is.

So we basically learns stuff we already knew: 6M6 rev limiters are too low and stock impellers suck.

Since we couldn't hook up on a setup or boat wake I tried a top speed run. Cavitation was still an issue, but the difference was impressive. So we also learned that running across the lake wide open bouncing off the rev limiter with the nitrous spraying did NOT blow it up. That's good news.

I've got another pump with a 15/19 Solas Impeller that we'll swap in next week. I also have a WSM CDI box with an adjustable rev limiter (anyone happen to have instructions for that??)

The siphon tube worked great and the bottle felt empty when I was done. I'll weight it to confirm that on Monday.

See ya,

Aaron

 

[kraqus]

I personally want to thank you for doing all this testing. I wish I could contribute somehow but I have 0 experience with Nitrous. Please keep us posted on your progress and get videos if at all possible.


Benny

 

[wsuwrhr]

Good man,

Do you mind if I add that to my sig?

Brian

So we basically learns stuff we already knew: 6M6 rev limiters are too low and stock impellers suck.

See ya,

Aaron

 

[ATS_Aaron]

Haha. We also learned that a 6M6 + 25hp basically equals a stock 62T so we really haven't done much yet. Just didn't want to risk a good 62T motor on this project yet.

I think I have Hoang convinced that this is safe....hopefully we'll get parts to do a dual carb setup this week.

Aaron

 

[ATS_Aaron]

I made a little extra time for the nitrous ski this week. We put an Impros modified Solas 13/17 impeller in there I noticed the driveshaft splines looked pretty bad...I really knew better than to try and use it....but I did anyway...

I got 2 kits on the bottle before it finally stripped out the driveshaft. I don't blame the nitrous because it was pretty messed up even before we started this project. I'll swap it out for another driveshaft and midshaft.

Tonight's results were pretty promising. Right now it's a STOCK 6m6 with a 25hp shot.
It felt WAY better than a stock 62T so we are definitely on the right track. The bottle pressure is probably a little low because of the water splashing on it and stuff. I'll get a bottle gauge on there for the next ride. We might need to jet the fuel a little leaner because of the lower bottle pressure.

See ya,

Aaron