I/O to outboard conversion

Timmyboy05

Recruit
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May 17, 2019
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3
I have a Grady White 197 Tournament I/O that has a Mercrusier 470 and am considering going with a bracket mount outboard. Can some of you with this conversion give me pros and cons? Thanks...
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
11,798
Cost, late model outboard are expensive, unknowns, will the boat have correct balance, it is a lot of work for unknown outcomes.
That boat would be well powered with a 4.3 V6-4bbl if you want to get away from the 470 engine but you have to change the front engine mounts, but might be less work than an outboard conversion and would certainly cost less.
 

racerone

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Dec 28, 2013
Messages
36,032
Getting rid of the 470 is a good move.------Big outboard on a bracket won't upset balance very much if any.
 

dingbat

Supreme Mariner
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Nov 20, 2001
Messages
15,413
The Grady 190 is the outboard version of your boat (197).

Balance will actually improve with the weight reduction. Ride quality will improve significantly with the bracket.

The hull is rated to 200 hp with the outboard. Transom height is 20”.

Ran a 204C for a number of years with a 175hp (rated to 230 hp) on the back. Great boat but got 2 footitice. Currently running a Grady 226
 

kcassells

Fleet Admiral
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Oct 16, 2012
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8,575
You animal. You can do it! Post alot of pics.
Transom beefed up and bracket needs right placement.
Have fun!
 

mickyryan

Rear Admiral
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Apr 18, 2016
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19 ft is kinda small to be hanging engine even further back on a pod, at least that's what they (guys that make the Bracket kits)told me about my 19 footer that it would change ride of smaller boat and not to do it
 

tpenfield

Moderator
Staff member
Joined
Jul 18, 2011
Messages
17,620
Pro's
Ditching the 470
Outboard conversion is a good move.

Con's
Gotta be done right
Might need some tweaking to get the proper balance point, both at rest and in motion.
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
15,413
19 ft is kinda small to be hanging engine even further back on a pod, at least that's what they (guys that make the Bracket kits)told me about my 19 footer that it would change ride of smaller boat and not to do it
In effect your adding 2’ to the length of the boat. A 21’ doesn’t ride like a 19’

What is the issue?
 

mickyryan

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Apr 18, 2016
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In effect your adding 2’ to the length of the boat. A 21’ doesn’t ride like a 19’

What is the issue?
because you are adding 2 ft and then throwing a weight back there on that 2 ft the center of gravity is thrown off a lot more in smaller boats is what they told me larger boats more forgiving.
 

mickyryan

Rear Admiral
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Apr 18, 2016
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again i wanted to pod a 17 footer and they advised against it so i made it flat back instead of having the cutout for outboard and using a long shaft engine. i wanted the swim deck for cooler storage:)
 

huggyb1972

Petty Officer 1st Class
Joined
Apr 1, 2013
Messages
230
The best thing I ever did on the 19 ft aluminum I had was to put a bracket on. It really made the boat work well and gave me all that extra space back. I would've put a bracket on the Bayliner I'm rebuilding currently but it wasn't in my budget for this year. I left the stern equipped well enough it could happen later though.
 

dingbat

Supreme Mariner
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Nov 20, 2001
Messages
15,413
because you are adding 2 ft and then throwing a weight back there on that 2 ft the center of gravity is thrown off a lot more in smaller boats
Big difference between “pods” and brackets. Brackets add boyancy to counteract the weight.

Let’s not forget that the I/O weighs (~ #750) verse #470 for the F150 outboard

 

huggyb1972

Petty Officer 1st Class
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Apr 1, 2013
Messages
230
Big difference between “pods” and brackets. Brackets add boyancy to counteract the weight.

Let’s not forget that the I/O weighs (~ #750) verse #470 for the F150 outboard

Pod/Bracket that term is used pretty loosely from what I can see.
 

mickyryan

Rear Admiral
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Apr 18, 2016
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Yes i see the weights,one is inside the boat adding weight like a keel other is hanging off backwith all weight furthest from the cog, both are taken in consideration when a boat designer designs the boat the pod/bracket moves that weight even further back
 
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