X-dimension
 

I have a 29' Essex Alandra 5300lbs v-bottom. My x# is 6.50" to 6.75". The boat comes on plane quick with little or no bow rise. Will only take a little + trim. Is the outdrive set to low. I think the boat is slow with the HP500efi 60-61mph with bravo 1 22p. I never bump the rev- limiter. No step's just a notch about 5' in the delta pad. No hook on the bottom, looks flat. 23 deg. deadrise & 40 entry. Help!!!
Thanks, Mike

help, i want to have a 3.3 whipple installed but not if i need to fix the drive height first $$$

When you measure your x-dim how are you doing it? You should have a 2 digit number, not a single digit.

http://www.offshoreonly.com/forums/s...highlight=xdim

prop shaft center line from bottom of hull. I think it should be at 3.5" + or - .
Thanks

You need to measure from the second bolt hole down on the transom to the bottom of the hull. Use a strait edge on the bottom of the hull's lowest point to measure to. (measure strait down to it, not at the angle of the transom or you will be off some) The number should be in the 15-17" range. You can measure up from the strait edge to get an idea of which bolt we are talking about. if you are confused.

I will check it this way today.
Thanks, Mike

The distance is 17.25" with this method. When i lay the straight on the bottom of the hull. There is a little dip about 4"-6" from the transom, maybe .060 is that enough for a hook ???
Thanks, Mike

X dimension is not really what matters as much as propshaft height in relation to the hull bottom. I doubt you'll change the actual X dimension. You would have to raise the engine and recut the transom for the drive to do this.

Simplest thing to do would be to raise the propshaft height by changing to a 2" shorty lower. This would put the propshaft in the 4.5 inch range which should be about right.

If you have access to a short drive, try it. But on a 60mph boat I don't see it helping a lot and I would not spend a few grand just to try it. Your X-dim is pretty good for not being surface piercing. If you raise the drive you will lose some planning speed, and maybe the handling.

.060 is not bad at all. I would weight the boat, it might be heavier than you think. A mirage plus 23 may help you as well

A whipple should get you to 70mph just the way you are. A short drive will never do that.

BTW- your steering may need an upgrade as well at 70+

you measure from prop-shaft center to bottom of hull with EVERYTHING parallel! or an easier way,,,level.

you are way deep my friend...and way too deep for a 4 blade...

i would not bother with a 2" shorty...still too deep...move the engine and use spacers to come back down.

SC'ing that engine w/that drive, x-dim, hull/system configuration will only bring you problems and very little speed...

good luck bro