Mark IV Block Question: How big can I go???
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Hello everyone.... I have two boats... 1988 and 1987 Donzi Z-33's and am planing on rebuilding the stock Mark IV blocks in at least one of the boats.
Do you know how much I can boar this thing out without getting into trouble?? Also, will a 4.25 crank just drop in or will there be machine work involved??
Not trying to drop a whole lot of cash here on new blocks...
Your thoughts are appreciated...
Q
Do you know how much I can boar this thing out without getting into trouble?? Also, will a 4.25 crank just drop in or will there be machine work involved??
Not trying to drop a whole lot of cash here on new blocks...
Your thoughts are appreciated...
Q
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you can bore out to .060, I would only go to .030 if the cylinders clean. But before I spent a lot of money I would look in to a 425hp HO 454 crate motor. I can get you pricing. I put two of them in my 29 fountain and they are running strong. Do you have any pics of the 33 Donzi. I had a 1976 Donzi sweet 16 with a 350 motor one nice boat.
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here is a picture of my boat... it is the 1988 I had planed on selling it for 15K and had a lot of people looking... but no cash on hand.
Shoot me the price of the HO motor... and we can go from there.
Also, Do you know if a Mark IV will take a 4.25 crank?
Thanks!
Q
Shoot me the price of the HO motor... and we can go from there.
Also, Do you know if a Mark IV will take a 4.25 crank?
Thanks!
Q
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It will take a 4.25 stroke crank. You will need machine work on the block for clearance. You also will need new rods and pistons. If you buy a cheap crank you most likely will need addition machine work.
Been there done that. Good advise on the crate motor. You will end up spending that much money on a rebuilt.
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Forgot to ask, boat looks nice. Is that a single or twin?
15k sounds like a good price for that boat
What state?
JIM
15k sounds like a good price for that boat
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What state?
JIM
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Originally Posted by 1BIGJIM
Forgot to ask, boat looks nice. Is that a single or twin?
15k sounds like a good price for that boat
What state?
JIM
15k sounds like a good price for that boat
![Big Grin](/forums/images/smilies/biggrin.gif)
What state?
JIM
I am located in South Carolina... If you'd like more pictures please let me know....
thanks!
Q
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Originally Posted by 1BIGJIM
what drives are on the boat now?
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I put a 454-425 HO crate motor in my Donzi Criterion, and I gotta say it's the only way to go. GREAT engine for the money.
JH
JH