Griff

To raise the X dim, you have to pull the engine and remove the transom assembly completely. Then figure 2k to have it glassed and gel coated. Then raise the engine and redrill the transom. This is then permanent and still an experiment. If it doesn't work, you will need to buy spacers.

You can pick up a used -2 shorty lower for under 3k and have it on in a couple hours. If it doesn't work, switch back and sell the shorty and you're out nothing but a hundred bucks for lube and gaskets.

Too Stroked

A "shorty" lower is definitely the easier way to go, but let me offer an opinion here. From what I've seen, generally speaking, under about 75-80 MPH, raising the x-dimensaion doesn't do a whole lot for speed. And this comes from a guy who's always run outboards with jack plates. So I can easily change my effective x-dimension.

The cheapest speed in this case - probably a 4 blade prop.

Dave M

He mentioned in a previous post that he has a King Cobra (KC) drive. I don't think you can get a shorty drive for that setup.

I don't want to burst your bubble, but I would look for a different hull if you want speed.

jeffswav

I gained about 3-4 MPH with mine. I raised it 3", I am now running 74. His drive is really deep, he is trying to make his more like what is coming out of the factory today. Most boats are now being built with the prop 4 to 6" deep. I agree a shortie would be easier than the glass work. My transom was rotton so I just cut my hole 3" higher.

Too Stroked

Very unusual to gain that much speed. Trust me, I've spent whole days out on the lake with dozens of props and wrenches to raise and lower mine on several boats. Hydrodynamic drag is what you're aiming to reduce with this type of thing and at lower speeds, it just isn't the most significant issue - or the cheapest to cure.

And remember, he has the dreaded King Cobra drive so he's stuck with "the expensive option" to raise his propshaft up.

Baja_man

By limiting the amount of drive exposed to this does it not help the hydrodynamic drag? Also does thrust and prop slip play a factor as well?

Itsallgood995

Yes, I do have the King Cobra drive & converting everything then buying a shorty is out of the budget. Its very surprising with the various results. Some guys put a 2” shorty on with no improvement & others report +10mph. I talked to a guy earlier who said he saw a boat pick up 7mph by only going up 1”. Another picked up 12 by going up 4”. Jeff saw 3-4 by going up 3”. Seems like a crap shoot on what the results may bring. Guess I’ll expect the least & hope for the best.

Anyway I already have the drive, motor & transom assembly out. Met a recommended local @ lunch & he quoted 800.00 to patch & move up the cut out. Still want to get a second bid from another recommended local later this week.

Haven’t ruled out doing this myself yet to save some cash if there is a decent savings. Any guess on an approximate materials cost … 200.00-300.00?

One last thought. Does drive heat go up with less drive in the water?

Will I need to think about a drive shower?

jeffswav

I have always used a drive shower, even when my engine was stock. Raising the x dim should not hurt the drive. In fact you would most likly use less trim and have less wear.

Panther

Doing the work myself, raising my X 2" on both engines cost me something like $1500.... The man-hours were a LOT though...paying someone would have cost a ton more...

It was either pay $7K for shorties or $1500 in supplies and do it myself... I chose the latter and gained 4-5 mph on the top end and 3-4 mph in mid-range.
http://s706.photobucket.com/albums/ww64/Fungarten1/

baywatch

Frank, nice chat'n w/ya today. How is yours getting on plane with the x up 2"? Per our conversation I'm thinking the shorty might be the direction I need to go (either that or trailer my boat to NJ to your place and let you do the work LOL).

I definately don't want one of those boats that won't get on plane if it is full of fuel and I have a head wind.