Extension Box ?

[BlownHowardCat]

26 ft howard cat Teague 800 hp Teague bravo XR....What advantage or disadvantage if any would there be installing an extension box ? What kind of speed or any other gains could be expected by pushing the drive back ? Current top speed is 106 with 1.35 gears 28 labbed prop by R&R prop.

[Craig]

One drawback is that you have to convert over to full hydraulic steering if you don't already have it due to the positioniing of the drive. Check with Howard and see if they've ever done one. Getting the drive further back in cleaner water should see some improvement, not to mention they look cool :D
Craig
[ November 28, 2002, 08:44 AM: Message edited by: Craig ]

[hcb26]

:p BlowenHoward Cat, I have tossed that ideal around for awhile, I know there is a Howard Cat that has a Imco stand off on it. Its all Red with a twin turbo motor in it, Ive heard it runs pretty good. This year I might try putting a standoff with a 2" shortened drive, and see what kind of MPH I pick up.

[dorC]

By using the box, you'll put the prop in deeper when planing. This is benefical with high prop shaft heights. You'll be looking for a prop height that will be 1-2" ABOVE the bottom. This is because the angle of the boat when it's on plane will put the prop back in. The water will also flow upwards slightly to meet the prop. The prop being further back will give greater leverage on the bow and it will make the boat behave like a larger boat-with out the weight penalty. The hydraulic steering shouldn't be an issue as your current speeds already mandate full hydraulic. You can reuse your existing rams and either use the IMCO wing plates or a standoff. Please realize that with these high shaft heights, that I've heard of people snapping the prop shaft with a mere hp500. Something to remember on reentry.