Thought I would start a new thread rather than hijack someone else's. Here is some video footage of the x cats running with 400r's.
The Austrailan boat has it right. If the video does not play I had to tape the blank box and it appeared.




https://www.facebook.com/nonsolomare...7962075004233/

Nice Video Ron, Guess all that extra weight doesn't matter that much there. They seemed to have balanced their rigs pretty nicely. Wonder if they have any balast added to the front end.

If you look close most of the boats have filled in the notch in the back, so they run better in the rough.

The Gold Coast boat looks a bit bigger?

They all sounded pretty good though.

Gold Coast is a Doug Wright so it should be the 32.

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Photo Credit: xcatracing.com

Doug Wright actually asked Gold Coast how they balanced the boat with the additional weight of the 400Rs. They replied it was balancing well and that no additional ballast in the front was needed for flat conditions. So does this imply that they have ballast up front and didn't have to add to it or that they have none and didn't need to put some in?

Changing the rig from 2.5L to the 400's is a major shift to the rear in CG.

When Bam had Ron/TNT Marine redo his 28' SKATER with the XS' the CG shifted. JT's fix was to drop off 2x 80lb sacks of concrete (1 at the front of each sponson). We all know JT is a bit of a magician on throttles but his exerience setting up a boat is to notch and would have known how much that amount of weight would influence a pleasure boat and that it was required...

A bare bones race hull would indicate an exact amount of weight has been added or shifted forward within the boat to get them to fly true depending on each teams preference on how to counteract the weight of the 400's.... and a lighter boat is a faster boat when the power is equal on efficient hulls

We may never really know for sure. Most race teams keep their set ups to themselves and not share anything. There was ballast and a ballast tank in the Mobil one boat and no one knew anything. I am sure they did something in the rigging. You cannot hang that kind of weight on the back and not do something.
Regarding the step in the transom the set back acts like a step if the motors were mounted on the back of our skaters with no set backs.

Great thread, Ron! Regarding the transom setback, it is my understanding that steps are there to aerate the hull to release it from the water. If so, what is the effect of the setback? It appears that it allows water to rise behind it which effectively puts more of the gear case bullet into the water stream?? and give more leverage to the force of the prop??? As you recommended, hopefully soon I will start testing CG changes on my Skater. I was more than impressed with the attitude of the X-Cats!