1970 Formula 233

[Mr. Tom]

Anybody interested in my restoration??

[whitepointer23]

where are the rest of the pictures.

[IMP-ish]

I'm interested. What have you done so far? Post some photos please!

[powerabout]

a great boat!
what power did that have in 1970?
215 II dr?
pair of 150 I dr's?

[Mr. Tom]

Here are some more pics.

It is a 1970 Formula Thunderbird F-233 Deluxe Fisherman.

It has been sitting for a few years, after a gimbal failure due to corrosion. It has been used in the past to fish Salmon and Tuna off the Pacific Coast here in CA.

It has twin fresh water cooled 165hp Merc 4.2l straight 6’s, with the early (or so I am told) #1 drives. (preload pins).

I was going to tackle the rehab of the boat, but dropped it off at the boat shop near my house instead.

[Mr. Tom]

So as it sits now, engines are out, transom stripped.
Found a new pair of transom brackets, drives being rebuilt.
Hope to have paint on the engines soon, as well as clean up the bilge and redo the bilge pumps.

[powerabout]

Whilst they are rebuilding spend the extra money and get a counter rotation lower for the port drive.
It makes a huge difference to the boat when it is on the plane

[Mr. Tom]

I have already looked into that, and it will cost about 1k, now or later, so I'm going to wait till next season. Will it make that much of a difference?

[Mr. Tom]

pulled the bow rail off this weekend, and shined the gell coat up.

[powerabout]

Originally Posted by Mr. Tom

I have already looked into that, and it will cost about 1k, now or later, so I'm going to wait till next season. Will it make that much of a difference?

The boat will not run level when on the plane without it.
When you run in the rough it will always rolling to port.
EDIT can be fixed in calm water with tabs buit as soon as the tab comes out of the water over it goes.
Tabs still are useful when running with big wind on the beam as vee's roll into the wind

[IMP-ish]

Originally Posted by powerabout

The boat will not run level when on the plane without it.
When you run in the rough it will stop always rolling to port.

OK, I need some physics 101.

How much more would this boat with twin non-counter rotating stern drives roll to port than if it only had a single prop?

[powerabout]

single prop you dont really notice it
remember for this size boat the single prop is the same diameter as a twin rig

[Mr. Tom]

So I checked into it again. This boat came this way, and a c/r lower is not available for this drive....

Not saying its right... but it will require a different drive for that side to get it done....
I just don't think its in the budget right now.

[Mr. Tom]

Engines and Bilge cleaned up. New Manifolds and risers on the way.

[IMP-ish]

Last night I was failing to wrap my head around how much the 15 or 16" offset of each drive and its rotational foce would affect the rotational force on the boat. I have never seen this analyzed with maths - I guess the people curious to 2 or 3 degrees enough to calculate it would spring for the cr drive!

I did run a twin smallblock v8 boat throughout the 80s. There were hundreds of boats in the 80s running without counter-rotating drives. The cr lower unit was introduced in 90 or thereabouts. (could be off on the year) Every time I came up on plane and trimmed out the drives I would give the starboard trim button two or three extra clicks to level out. I thought about getting a counter rotating lower and new prop for that drive, but always found something else to spend the money on until I got a boat with bravos.