Bored out 3208

Jonathon

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Is it feasible to bore out a 210 hp 3208 and get 375 Hp or more out of it and would it be worth the $ and effort
Or would it be more realistic and more economical to replace with the 210 with a 375 hp and call it a day
Understanding we cannot get a brand new 3208 anymore and would try to buy one used and have it rebuilt anyway
Any ideas on the above ?
tnx
Jon
 

Genius

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Sounds like gas motor thinking to me. I’m not familiar with the 3208 but check out boat diesel.com for what needs to be done to get more hp. It’s not boring out I bet. It’s more fuel and cooling capacity most likely. Easiest would be to find a higher horsepower running take out and install. Why rebuild a running take out???
 

Keelboater

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Bore out for more HP? That gets you minimal gain. I believe all of the 3208 motors share the same bore & stroke, but don't quote me on that. The HP comes from fuel pump, injectors, after cooler, turbo size, correct heat exchanger size for the HP, and sometimes the cam. The natural has a flat tappet cam whereas the turbo motors have roller cams. Granted they all look very similar at first glance, they are quite different. I have a 320 HP 3208 that is complete. It was a running take out that most likely is ready for a rebuild if you are interested. No aftercooler on this one. The aftercooler came on the 375 HP and higher models. Anything over 375 HP on these motors is taking away from engine life if you tend to run it hard.
 

Kailua Kid

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Sounds like gas motor thinking to me. I’m not familiar with the 3208 but check out boat diesel.com for what needs to be done to get more hp. It’s not boring out I bet. It’s more fuel and cooling capacity most likely. Easiest would be to find a higher horsepower running take out and install. Why rebuild a running take out???
Genius is spot on. With diesels, to increase power, increase fuel; when you increase fuel, you usually need to increase cooling. You sho u ld be able to get 260 hp out of the 3208 block by adding a turbo, without adding an after cooler, since Cat sold a version of the 3208 in that configuration with that rating, I understand. I think to get 375 hp, you need the after cooler also. The 435 hp version I think uses more boost, and 15.5:1 compression, rather than 16.5:1 as in the 210 and 375. You can get over 400 hp out of that block without a turbo by increasing fueling, but to do so without sacrificing longevity, you will spend more than what you would spend to switch out the 3208 for a running take out of a higher output engine (head and stud upgrades, cam upgrade unless yours already has the forged steel cam, etc.) Sign up for boatdiesel.Com before you get too far along the decision path and save yourself from costly mistakes, is my unsolicited two bits.
 

Jonathon

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Glad I’m talking to the right crew
Thank you for the input
I will check out the diesel website
Appreciate all the intel this community has to offer
Stay healthy everyone
Jon
 

ARC

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I’m guessing a 3208 375 hp long in the tooth would cost you about $5k. Then another $5 to freshen it up. I think that’s the best way to go. There will be no surprises.
 

Longfin

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Hey Jonathon,

I'm running a 375hp 3208 that's never been remanned. I'm told it has about 6k hours as the hour meter was inop when I bought the boat. I'm considering repowering next winter. I'll probably be selling bobtail if you have any interest. It runs strong but smokes on startup. Cleans up quickly at cruise. My thinking is valve stem seals. Don't know the price as yet.

Stu
 

aegus15

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Hey Jon, put a call into T & S Marine in Maryland, they rebuild (best at it imo ) and probably has a couple on the floor ready to go .
Bought from them 3 years ago and couldn’t be happier.....
 
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