Killer Kat (Build Pics Updated)

Hi Woodie,
Oops, did not know the details. Give my apologies to your better half.
Moofy

Even after you putting it like that... I still can't see it, But somebody seen it, maybe they need someone to introduce them to a FRIND.... if ya know what I mean... :laugh:

Moofy.

Just pulling your leg. I'm sure you can take it.

Cheers!

Woodie.

Hi Woodie,
I sure can. I did not get these wide shoulders just from growth.
Moofy

I have a tech question. Which would be better for the drive system, 2 struts set as surface drives on the inside edges of the sponsons? Running submerged in this configuration? Or running a set of actual surface drive units on the bottom of each sponson?

Isuzu.

I am not an expert in this, but I am sure that you should never put the drives at the end of the sponsons. In that way the propellers will sit in the middle of "spoiled" water and have very little effect.
Put them between the sponsons. For my part I would put them deep and not surface-piercing. This should transmit more effect directly to the water. In my opinion "roostertails" are pure waste of power.
But thats just the way I would do it. As with the double sterndrives on my mono.
Maybe others have better solutions?

Cheers!

Woodie.

I ran my Shockwave in both configs... and the surface drive set up, with the same prop, 6717/3, was the faster set up. So, I don't know... that's why I threw the question out there. Because cats are new to me, and wanting to go fast instead of scale standoff, I need all the help I can get!!!! :dry:

Don't know if this will help or not ?

When we run SURFACE DRIVE props we obviously need to find the correct loading for engine used playing with props size.
But once we find the correct prop, getting consistent performance from said prop requires depth each blade go's into the water be fairly consistent as well.
So .... a surface drive prop say in a cat that sits within tunnel out back gets buried deeper at slow speeds and drier as hull gets on step at speed.
A surface drive prop say out the back of a twin cats sponson or transom of a mono has the water shearing under the ride surface and depth in which props blade contact water a lot more consistent :woohoo:
So while you may view a prop out in open undisturbed by ride surfaces as the better performing, it also is it's curse for reasons described above

Thanks Scott, I understood what ya meant. But I'm just looking for top end speed, not getting out of turns fast (heat racing situations) just flat out straight speed. Under these conditions, which do you think would give the fastest speed? The only "prop testing" performed would be for top speed.. :woohoo:

Well obviously if running a single prop on a cat center of tunnel is the ONLY place to be :silly:
Going TWINS in a cat given enough transom width and width within tunnel for side by side props ... drive shafts and stuffing tubes would be straighter and have less drag NOT having to bend outward and downward getting into position to exit trailing edge of sponsons

That answer your question ?