Twin out-board cat discussion

[F1 madness]

Awsome guy's. Looking forward to more pictures of dual outboard cats. Here's mine for some inspiration. Ran it this past weekend. I have a lot of work to do. All it did was porpuse. Could not get it on plane. When I hit the throttle it wanted to flip sideways. Probably will have to convert to counter rotation. I think too I had it way over propped.

[ATTACH]29796[/ATTACH]

[ATTACH]29797[/ATTACH]

[ATTACH]29798[/ATTACH]

[ATTACH]29799[/ATTACH]

Man thats cool,what outboards you using on that they look ace.
Hope you get it sorted be sure to get a couple of vids,be interesting to see it go

[DPeterson]

Awsome guy's. Looking forward to more pictures of dual outboard cats. Here's mine for some inspiration. Ran it this past weekend. I have a lot of work to do. All it did was porpuse. Could not get it on plane. When I hit the throttle it wanted to flip sideways. Probably will have to convert to counter rotation. I think too I had it way over propped.

100_2921.jpg

100_2922.jpg

100_2923.jpg

100_2924.jpg

[F1 madness]

If you replace the stub shaft assembly with one from Hyperformance Products, you'll have plenty of length, and a stub that will last a LOT longer than the standard K&B:

http://hyperprod.bizhosting.com/psa35.html

Cool project.... I'm going to be doing a dual outboard conversion on a ProBoat Miss Geico later this summer, but I'll be using dual ProBoat Stiletto Outboards on it with dual BlackJack or Stiletto power systems... Should be a fun project!

Alrite Darin,i look forward to seeing your version with awesome looking outboards,and the geico.
Im looking forward to start the actual build,but for now its just working all the measurments out,im pretty sure i can get it to look very simular to the 1 in the pic,but with my own touches (hopefully LOL)
Will keep posting with updates maybe even a few pics once drawn up.

[Darin Jordan]

Thank you very much for the info Darin! I use my outboard on my rescue boat and I would love to use a 447/3 on it.

No problem... that stub has about 1/4" or so more length. 447 should fit without any trouble.

[BakedMopar]

Thank you very much for the info Darin! I use my outboard on my rescue boat and I would love to use a 447/3 on it.

[Darin Jordan]

I can only get a 445 on. The 447 and up has a longer hub and I can't get the whole nut on. Not too sure inexact measurements but I can gt them for you later if you need.

If you replace the stub shaft assembly with one from Hyperformance Products, you'll have plenty of length, and a stub that will last a LOT longer than the standard K&B:

http://hyperprod.bizhosting.com/psa35.html

Cool project.... I'm going to be doing a dual outboard conversion on a ProBoat Miss Geico later this summer, but I'll be using dual ProBoat Stiletto Outboards on it with dual BlackJack or Stiletto power systems... Should be a fun project!

[F1 madness]

I can only get a 445 on. The 447 and up has a longer hub and I can't get the whole nut on. Not too sure inexact measurements but I can gt them for you later if you need.

that would be a big help cheers bud,iv got some cf props the 42mm,45mm,47mm, all have the same length hub LOL

[BakedMopar]

I can only get a 445 on. The 447 and up has a longer hub and I can't get the whole nut on. Not too sure inexact measurements but I can gt them for you later if you need.

[F1 madness]

Don't take it the wrong way. I was asking cause I would like to run a bigger prop on mine. I'm sure anything is possible if you have the resources.

not taken wrong way,whats the biggest prop you can get on the standard shaft.
(how long is the hub is the max)

[BakedMopar]

Don't take it the wrong way. I was asking cause I would like to run a bigger prop on mine. I'm sure anything is possible if you have the resources.

[F1 madness]

I am not familiar with the O.S. lower unit but the K&B stub shaft doesn't allow for props with larger hubs (447's and up). Is there a way to lengthen the stub?

Edit sorry I meant OS lower unit.

not sure,if i cant get that size prop on the stub that come with the unit ill have some machined at my local engineers,whose a friend of mine,nothing is impossible

[BakedMopar]

I am not familiar with the O.S. lower unit but the K&B stub shaft doesn't allow for props with larger hubs (447's and up). Is there a way to lengthen the stub?

Edit sorry I meant OS lower unit.

[F1 madness]

[QUOTE=Fluid;208671]I run a Scorpion 4025/6 on 6S and it needs a lot more prop than an x447, even in a single motor 35" cat application. I know you want to run counter-rotating props, but you won't like the low speed from the x447s. Mine runs well on an x455, but if you want more than 45-50 mph you'll need either more pitch or more motor.

These motors are rated by Scorpion at 100 amps tops. I've run mine in the 130s and it doesn't get too hot, and in an OB application it may work okay. But remember that these motors are designed to run in an open helicopter and drawing over 100 amps continuous may shorten their life - or not.

Cheers bud,which motors and props would you go for then if i wanted hit min 50mph

[Fluid]

I run a Scorpion 4025/6 on 6S and it needs a lot more prop than an x447, even in a single motor 35" cat application. I know you want to run counter-rotating props, but you won't like the low speed from the x447s. Mine runs well on an x455, but if you want more than 45-50 mph you'll need either more pitch or more motor.

These motors are rated by Scorpion at 100 amps tops. I've run mine in the 130s and it doesn't get too hot, and in an OB application it may work okay. But remember that these motors are designed to run in an open helicopter and drawing over 100 amps continuous may shorten their life - or not.



.

[F1 madness]

Sorted im just starting the drawings now for parts needed to start putting it together,i think this is gonna be a fun and interesting build,and my biggest 1 yet LOL
will keep you posted on progress