Offshoreonly.com - Land and Sea Stern Jack

Offshoreonly.com (https://www.offshoreonly.com/forums/)

- Drives and Lower Units (https://www.offshoreonly.com/forums/drives-lower-units-217/)

- - Land and Sea Stern Jack (https://www.offshoreonly.com/forums/drives-lower-units/333818-land-sea-stern-jack.html)

My boat is a 1988 Baja Islander 216 that I am getting ready to pull out of long term storage. 350 mag in it now but I am going to build a 400sb if the block I have is good or a 383 if its not. I would like to have an honest 65+ mph boat

How fast does it go now ? Just wanna see what it will take to reach your goal.

Quote:

Originally Posted by SB (Post 4394280)

Sorry, I was setting you up on that question to see what your answer was.

On most all 60+mph small sbc/alpha boats , will gain 5+mph with a simple swap to an SS.

Boat I'm tweaking now, gained 7mph, and it is now over revving the engine by 700rpm with same prop that was on the regular Alpha. So, we are exxpecting more when repropped. 65 to 72.8 so far, conditions per conditions. Just drive swap.

Regular Alpha's really start needing improvements in the 60's. Schit, I've even had Alpha boats respond with Hydromotive nose cones when running in the 50's.

I had a Alpha boat gain 2mph when 1/2 the skeg was broken off from a rock.

Well, that may be true, but I'll add one big qualifier. If the standard Alpha drive is "buried" (mounted fairly deep) on the hull, you may reduce drag enough to see some gains. On any boat with the drive mounted further up the transom - like the Villian - there simply isn't enough difference in drag. This may explain how some folks say they got more speed gains on "family boat" style hulls. Fair enough?

Oh, and one should really look at how much the drive swap costs compared to how many (if any) MPH are gained. You may find that's a pretty expensive proposition.

Most sbc/alpha's have the drive buried. Including sport boats. Many have the propshaft 7-7.5" under the bottom of the transom. Did not know that on the Villian's. Thanks.

Drive cost is not too bad. $2500-$3000. And it's a direct bolt on.

However, trying to find one can be difficult !

I figured that raising everything up would give the benefit of the SS without spending money on and breaking a hard to find and expensive drive. I have a complete Alpha Gen 2 setup that I plan to swap on. Standard Alphas are cheep and available. The boat only ran in the low 50s the way it was but was not set up and 350 mag with over 600hrs

I have the original drive and gimbal off the boat. Can anyone give me a measurement from the bottom of there Alpha transom assembly to the bottom of the boat? I know its not the ideal way to measure but it would give me a rough idea how deep my drive is mounted. I could also throw the alignment tool in and measure what the true x dimension is.

I am pretty sure I have that coupler for the stern jack. I will take a pic and post it tomorrow. Sold my old alpha SS a year or two ago and converted it back to the standard coupler before I shipped it.
I gained significant speed adding the stern jack to a 21' scarab and even more speed when I went to the alpha SS.
The stern jack seemed to work well on certain hulls but agree that it causes other problems the biggest being needing external steering.

papps, that is great to here. If you have the coupler I will at least have a complete unit. I am guessing that's what happened to the one that should be with this setup, probably sold away with the drive. John

[ATTACH=CONFIG]549731[/ATTACH]

That is the coupler you are looking for above?