73" Cat rigging help!!

[NitroEd]

First of all, I have to say that I am amazed at how popular this hobby is. I never would have imagined that model boat racing is world wide. My buddies bought me a Miss Llumar as a bachelor party present and I've researched it from there. Naturally, we are gear heads and want bigger and faster now. We have some offshore boating experience and are really familiar with it. I've been particularly impressed with these larger scale boats that people are building.

Well, through some contacts, I've been offered a free 73" cat hull. These are hand built, not a particular brand. They've been paterned off of a Skater hull.
So, my question is, I would like to know what everyone thinks of what to buy for the rigging. Motors, servos, hardware, pipes.......

I've done some research but like I said, I'm pretty green.

[Micho523]

For the engine, i would reccomend either a twin quickdraw setup ($$$) or go to www.mhzusa.com and get their Blata 40 marine ($$$). Power for any hull that large will be really expensive, at LEAST $1000 for halfway decent speed. I think the blata would do the trick, or if you have $4428 to spend on an engine, get the MHZ Rotax 125 MAX geared. That is the same engine found in the go-cart racers that can do 120mph!

[NitroEd]

I'm thinking of going w/twins. I may not get the most expensive motors to begin with. I was thinking of something stock and then upgrade later after I learn a little about running it.

[Micho523]

I suggest you go with a mid mod zenoah 260 if you are looking to save a few dollars.
http://www.bonzisports.com/mods.html

I honestly think that stock zenoah 260s will not be enough power to push that baby!

You may or may not need to have them counter rotating, talk to some of the seasoned experts about that.

I also have no idea how to get a zen spinning in the opposite direction.

Good Luck, and post some pictures!!

[NitroEd]

This will be a little while before I get started so I'm just researching out what to get. I see a lot of photo's that I like, but don't really know what I'm looking at as far as brand names. I would probably not go so big but the hull is free.

[Chris LaPanse]

Twin Quickdraws would be my reccomendation. 25cc's/motor would be pretty good, 35cc's/motor would be better, and 70cc twin cylinder motors would scream. This cat will be major $$$ to get going well (twin QD's are $1400-$4000, depending on which motors), but once it does have the right power source, it will absolutely be incredible.

Also - PICS. We live off pics, any that you have would be much appreciated.

[NitroEd]

Ya I know. I've got someone offering me a free hull and I wish it was a 50-60" so I didn't need as much motor to push the thing. I'll probably be machining my own hardware, so that will help. Has anyone taken Homelite or some other type of weed wacker motor and put a hop up kit in it? I'm wondering if it would be cheaper to build the motors rather than buy one.

[Micho523]

Even with all possible mods done to a homelite, you will only get about 4HP from them. The QD's with a tuned pipe on them put out almost 8HP. You could do ultra modded homies, but if you are going to mod engines yourself, get Zenoah's and mod those your self. You can get the same amount of power out of a well modded zen as you can from a QD.

[dadyo39]

There is a guy on jims rcboatdock site that has a73" cat with 4 260 zens in it there is video of it running and build pictures that might help you.

[NitroEd]

Do you have the link? I've been trying to sign up on that page and I keep getting denied.

[NitroEd]

I saw the quad cat, and I found a video of them starting it up. Pretty cool.

It seems that our biggest expense is going to be the motors. I'm thinking now that we'd be better of going with a 50-60 inch cat to keep the cost down. I like the idea of twins. I've been around the offshore boats a little and a buddy of mine used to have a 32' Thunder cat. Man that was a lot of fun.

But of course, THERE'S NO REPLACEMENT FOR DISPLACEMENT!

[Chris LaPanse]

Absolutely - that's why you need 70cc twin QD's ;)

[Micho523]

I cant find the Quad zen! Could you guys point me in the right direction???

[outlaw tunnel]

www.sonicracingaustralia.com makes the twin G260'S and the quad G260S i just got my self a twin its the black one thats on the web site
regards
ian

[sonicracing]

Hi Ed, 2 things will determine what Engine or engines will fit your 73" hull and that is how much room there is and what your budget can afford. I design and build a 73" catamaran in Australia which can use either a single engine in the middle, a twin with an engine in each sponson and recently a quad with 2 engines in each sponson. My hulls are specificly designed and built to accomodate these gas engines where as a lot of other hulls this size are not as they were originally designed for the smaller 90 class glo engines with a rear exhaust. Considerations need to be made for tuned pipes and spark plug height when fitting engines in the sponsons. The hardware I manufacture is also specific to my hulls and may or may not be suitable for other hulls of this size.

In time Ian will find out how user friendly his twin cat is with the ease of component removal for regular maintenance. There are lots of Videos (http://www.sonicracingaustralia.com/video.htm) and Photos (http://www.sonicracingaustralia.com/tc6.htm) on my website for these large cats.

Cheers, Danny.